paul

Rubber Stamp

A VERY SPECIAL CDAS RAFFLE

Thanks to our generous sponsor Canberra Marine, we'll be launching a special raffle at our December meeting

(Tuesday 17 December at the Harmonie German Club).

The prize is an 80 litre Aquatopia Total Marine Starter Kit.

This complete marine starter kit includes:

•80L Black Aquarium, Protein Skimmer, iological filtration Easily replaceable

media, 30w LED Lighting 3500LUX, Double cooling fan, Wide feeding lid

Stand, heater and a $200 voucher to spend at Canberra Marine to stock your new

display are also included.

That's over $700 in a single, winner-take-all, prize.

If you have ever been tempted to try marines, this is your chance.

So don't rely on Santa for your 2014 aquarium needs. Get

your tickets as soon as you can.

Tickets are just $2 and the draw will take place on 8

February at the CDAS Mega Auction. Tickets will only be

available at the December and January CDAS meetings and

at the Mega Auction before the draw.

THE MEGA AUCTION IS COMING

Yes! The first CDAS Inc. MEGA Auction of 2014 will be held on Saturday 8 February 2014.

Details are still being worked out, but the date and venue (Harmonie German Club, Narrabundah, ACT) are locked

in.

There'll certainly be truck loads of fish, invertebrates, plants and aquarium products available.

CDAS members should start considering what they'll be submitting

for auction.

As in previous MEGA Auctions, the club will purchase a wide range

of unusual and hard-to-get-items for the auction.

There will also be raffles (including the drawing of our Very Special

Raffle), giveaways and special offers on the day.

Non-members will be able to participate (in buying) by purchasing a

bidder's card or joining CDAS on the day.

Come along and bring your friends and family. Make a day of it.

We'll see you there.

STOP PRESS – NEWS JUST IN.

As you all know, this is a huge topic and it is daunting for most people, new to the hobby or otherwise. I

figured I’d put together a bit of writing and see if I can explain it as best as possible, because I feel it is important for anyone who is just starting up or has been running a planted aquarium to understand what is going on, why things happen and what you need to do about them. Hopefully, this is helpful to those who don’t quite get the intricacies of chemistry.

Just a note on the order of things included here: I put it so that inexperienced people can start with the first section first, it will explain the basics, the second section will explain the nitrogen cycle in detail, the third section will be briefly on CO2 and Oxygen, the final section will be on plant nutrients. I guess it is ordered from most known to least known and if you know a section, don’t bother reading it, I haven’t added anything ground breaking or experimental, I simply recapped the basic chemistry in easy to grasp terms.

1. The BasicsBasic Elements in the planted aquarium include- Iron (Fe), Magnesium (Mg), Boron (B), Copper (Cu),

Manganese (Mn), Sulphur (S), Nitrogen (N), Hydrogen (H), Oxygen (O), Calcium (Ca), Potassium (K), Sodium (Na) ,Phosphorous (P) and of course Carbon (C), I may have missed a few which I will edit in later, but these are the ones that I can think of as most important.

Ions- Charged form of an element or a compound (compounds being a series of elements bonded together ina fixed ratio). Ions can bond together to form Ionic Compounds. There are two types of ions Anions and Cations.

Anion- A negatively charged ion, examples include Nitrates (NO3-), Phosphates (PO4 3-), Nitrites (NO2-) and Sulphates (SO4 2-), Carbonate (CO3 2-)

Cation- A Positively charged ion, normally a metal (Ammonium is an exception, there are others), Examples include Ca 2+, Fe 3+ Fe 2+ (both iron, but differing oxidation states, will get to this momentarily), Mg 2+, H+ (hydrogen is mostly thought of as a non metal, I am content to leave it this way as an exception to the rule) and ammonium is NH4+.

Compounds- A chemically bonded species consisting of multiple different elements, can be ionic (Na + Cl - ),can be charged (SO4 2-, NO3 -), can be stable (H2O, O2, CO2) .

Bonding – There are multiple different types of bonding that go on in an aquarium, however I will explain onlyIonic Bonding. This is how ions come about. I will first use an example, elemental Magnesium isn’t particularly stable, it will react with most things (air, water, acid, your fishes poo), it can however stabilise itself by donatingits two electrons to another unstable compound, say sulphuric acid. You will never ever ever find Magnesium in its pure form in the aquarium, (call me if you do, I’d like to see it :P), however you will find Magnesium Sulphate in just about every aquarium. This is a Magnesium cation bonded to a sulphate anion, it is stable andwill dissolve in water due to being ionic (I can explain this more if someone wants, but this should be sufficient)

OK, with that out of the way, I will have a crack at describing water parameters.

pH

pH is a measure of the acidity of the water. A pH of 7 is considered neutral. At this point, the acid causing H+ ions have equal concentration to the base causing OH- ions. Hangon, what ‘s an acid and a base?

A substance is classed as acidic if it can ionise water by giving water a H+ ion, which will form H3O+, this however does not mean that any substance containing hydrogen will turn your water into a bubbling pool of acidic water, in fact most hydrogen containing substances are content to sit and do nothing. The compounds you have to worry about are called Acids, and they as a general rule, will contain a hydrogen that isn’t bonded

particularly well to the other part of the compound. Examples include H2SO4, which is 2 H + molecules bonded to an SO4 2- anion. This will disassociate (break up, separate, run freeeeee) in water which is what causes the water to become acidic, (this is what H+ ions in solution do, cause acidity).

Bases, by definition accept a H+ ion from water,ionising it to be OH-. Common bases include, NaOH.The Na + (sodium in case you have forgotten) and theOH- disassociate. The OH- reacts with a H+ ion in thewater to form H2O. When there is more OH- ions in thewater than H+ ions, this is when you have a basic pH.

(I may have lied to you about the ‘current’ definitions of bases and acids, but for our purposes, this is acceptable)

Ok, cool, so we know what bases and acids are now, but how do they affect us?

Well…

You know when you measure the pH of your tank, you get a number. This number could mean anything. Anything at all. But it doesn’t. It relates to the concentration of H+ Ions in the water. Why do we measure H+ ions and not OH-, convention. A pH of 7 is considered neutral, the H+ ions have an equal concentration to the OH- ions, everyone is happy (fish too). Any pH that is under 7 is considered to be acidic, H+ concentration is greater than OH- concentration. Any pH that is over 7 is considered basic, OH- is greater than H+.

The pH scale is logarithmic. This means that each number represents a concentration different to the previous by a factor of 10. For instance, pH 6 is 10 times more acidic than pH 7 (the H+ ions are 10 times the concentration). pH 5 is 100 times more acidic than pH 7 (fish aren’t so happy anymore). pH3 we are talking pure vinegar (even people aren’t happy anymore). pH 8, 10 times more basic than pH7 (most fish still happy). pH 10, 1000 times more basic (woah, what the hell are you putting in your water).

When you add acids to bases, they react, neutralising , to a degree. Adding NaOH (strong base) to vinegar isa little like peeing on a house fire, the resulting product will be a basic salt, I guarantee it. Adding HCl (strong acid) to NaHCO3(weak base) will leave you with an acid (carbonic acid H2CO3) and a salt (NaCl, table salt, yum, kidding don’t eat it, its mixed in with an acid). (HCl + NaHCO3 -> NaCl + H2CO3)

How does this affect the aquarium. Well, the pH in your aquarium is dependant on a number of things. Ill try to explain some, but others will require a google search.

Firstly, sources of bases in your aquarium. These include HCO3- (the hydrogen carbonate ion), this is due to dissolved minerals in your water like limestone (CaCO3 ) which will react with carbon dioxide in water (which isacidic, ill get to that I swear) to create the HCO3- ion. Plants also release the HCO3- ion when they are photosynthesising, this is a product of consuming CO2 (carbon dioxide) from the water column and releasing oxygen. There are countless other sources of OH- ions in your aquarium, these include shells, certain gravel, certain rocks, fish excretions (NH3 is a base) and tap water (thanks Sydney water). These aren’t a problem in the aquarium, due to buffers (again, I will get onto that later) which prevent large pH changes.

Acids, Acids are again, common in the aquarium. There are all kinds of organic acids that are present in the aquarium, these are metabolites of fish waste, secretions from soil, peat juice (for lack of a better word), present in food, put out by decaying plants, the list goes on. As a general rule, any kind of decaying organic matter will create some form of organic acid which could affect the pH of your aquarium. Another source of acidity in the aquarium is dissolved CO2, (CO2 + H2O -> H2CO3, H2CO3 -> H+ + HCO3-). Also, some tap waters are acidic.

Ok, so why is pH so important for your fish and plants? Various aquatic chemical mechanisms change vastly with differing pH’s and the toxicity of certain metals and compounds changes with pH, what does this mean for a balanced and safe aquarium? Not much, if you’re aquarium is balanced don’t stress, having a slightly acidic or slightly basic pH isn’t the end of the world.

If your pH is between 6 and 8, I see no problems with keeping fish. There is normally no reason to adjust yourpH unless you are breeding specialist fish or are experienced. If your pH is a bit high, you can add peat to yourwater, this will soften the water (coming up soon) and lower the pH by releasing Humic Acids. If your pH is too low, add crushed coral, shell grit, dolomite, etc ( a quick google search will tell you what is and isn’t viable).

The most important thing about pH is to prevent wild pH swings, a mildly acidic or basic tank wont hurt your fish, but pH that changes continuously will stress them, will wreak havoc on your tank chemistry and will be a massive pain. Basically, when you are testing for pH you are testing to see if it is liveable for the fish, and you are testing to see if it is changing with time. If it is changing, your tank is unbalanced and you have to do something to rectify it, whether it be plant more plants, take out that big bubbling rock, again a quick google search can tell you exactly what needs to be done.

As a general rule, don’t use pH Down, or pH Up to adjust your water whenever it is starting to shift, this is a bad way to control pH and a good way to have wild and random swinging pH’s that will stress you and the fish out, instead address the issue at the cause.

Naturally, in distilled water pH will swing quite rapidly for any number of reason, well, how do we prevent this?The answer is buffers. Which is the next topic.

Buffers

Buffers rely on a chemical system called equilibrium. Equlibrium’s are reactions that will proceed both ways based on the concentrations of the reactants and the products. An example of a common aquarium buffer is the HCO3- system. Most buffers rely on a weak acid (or weak base) and a salt of the acid. Bicarbonate systemisn’t an exception. It relies on a few equilibrium equations:

CO2 + H2O <-> H2CO3

H2CO3 <-> H+ +HCO3-

HCO3- <-> H+ + CO3 2-

CaCO3 <-> Ca+ + CO3 2-

The basis of this is that when you change one of the parts of the equilibrium, the others adjust so as to minimize the change. What this means in a very basic sense is that if you were to add acid to a solution buffered with CaCO3 and H2CO3, the pH change would be less than if you were to add it to an unbuffered solution. This allows the pH in aquariums to remain fairly stable despite the constantly changing H+ and OH- generated in the aquariums. This is handy, because during the day, plants generate HCO3- ions, but at night, they release CO2, this CaCO3 buffer prevents wildly swinging pH from day to night. This is the most basic buffer system in most aquariums, there are softwater aquariums with negligible amounts of CaCO3 dissolved in them, these utilize a different buffer system normally comprised of humic and other organic acids, I wont go into that because it’s a big side topic. Diana Walstad has however, if anybody is keen to get her book (I have it,it is excellent).

Before Moving on:

Please note, this is a thousand times more complex than I have explained, so don’t go adding straight dolomite or lime or anything of the sort to prevent pH changes. You will do more harm than good. Crushed shells, limestone, that kind of thing, is more acceptable, but research before doing so.

Well, you may be wondering, where does this Calcium Carbonate come from?

This brings us to the next topic

Hardness

There are two types of hardness, well, theres really not, let me try again, there are two measures of hardness. Hardness is I guess a hypothetical thing. The water isn’t physically hard. Its still a liquid. God I’m

funny. No? Ok… I will continue. The two measures are KH and GH. KH stands for Carbonate Hardness (or Karbonate, If that will help you remember it) and GH stands for General Hardness.

I am going to rely a little on Wikipedia here for certain numbers and reactions, so bear with me.

Carbonate Hardness is a measure of the dissolved carbonate (CO3 2-) and (HCO3 - ) bicarbonate Ions in thewater. It is measured in ppm which is equivalent to mg/L which isn’t at all equivalent to one dKH, the conversion factor according to Wikipedia is one dKH is equivalent to ‘17.848 milligrams of calcium carbonate (CaCO3) per litre of water (17.848 ppm)’. Carbonate hardness due to being composed of Magnesium (Mg) and Calcium (Ca) and other multivalent (more than +1 charge) metals is expressed as if all the carbonates came solely from calcium. Similarly, bicarbonates are expressed as if they were equivalent concentration of carbonates.

General Hardness is simply a measure of the concentration of multivalent metals in a litre of water, it is again expressed in a number equivalent to all the metal concentrations coming solely from CaCO3. It is expressed inppm of Ca 2+ or dGH.

OK, so the verdict on hardness is that hardness acts as a buffer to prevent pH changes. Hardness however, does also have the effect of increasing pH, the harder your water, the higher your pH. It also means that it is incredibly difficult to lower your pH should you want to breed softwater species or grow specific plants. In orderto lower your pH you have to adsorb the Ca and the Mg and the Carbonates out of the water first, this will soften your water and lower the pH slightly. Please note, softwater is more susceptible to water changes than harder water. A good method of lowering pH is peat, which will also remove Ca and Mg ions from the water and replace them with H+.

So, that's basic water chemistry 101. Yay new Topic .

2. The nitrogen cycle.Nitrogen is the most abundant element in our atmosphere, consisting of around 70% of the air that we

breathe and live in. So, what makes nitrogen so important. Well, N2 (diatomic nitrogen, the form found in the air) is possibly the most stable molecule around, it will not break down under most circumstances and it in its elemental form wont react with most things unless pushed (and by pushed I mean hundreds of degrees and thousands of pascals of pressure). So, why is it so important in the aquarium?

Well, because nitrogen is so inert, of course plants and bacteria have found a way to break it down. Nitrogen is included in almost all biological molecules. This includes fish food.

So, the fish eats the food. In its waste, it then excretes Ammonia. Fish waste isn’t the only source of Ammonia, decaying plants and most decaying organic material will release ammonia. Remember the discussion on pH before and the particular line, pH changes how things work in the aquarium? Well, this is an example of that. Ammonia (NH2) is deadly to fish, it is also however a weak base, which will react with H+ ionsto form Ammonium (NH3+) which isn’t lethal to fish (it also isn’t optimal, it is still in equilibrium with Ammonia and will more than happily revert at any given time). This reaction will only occur in acidic water however, so there needs to be another method of removing ammonia from the water.

This is where the nitrogen cycle enters, hopefully you’ve all heard about cycling. Wait you haven’t? Ok, let meexplain. Ammonia is introduced into the water column by some type of fish waste, bacteria on all the hard surfaces in the tank will process this ammonia, it will transform it into Nitrites (NO2-) through oxidisation. This bacteria isn’t present in the tank unless it has been cycled correctly. This bacteria is also very important, like your fish, and so shouldn’t be treated with chlorine or excessive changes of pH and temperature.

The bacteria serves to turn the deadly Ammonia into Nitrites, and this will allow the bacteria to flourish and breed. ( Because this is processing the Ammonia it will cause the Ammonium to break up back into Ammonia and H+ to be processed) Ammonia levels in the aquarium go down, the number of bacteria stabilizes and voila, your tank is cycled, ready to have fish and work through more ammonia.

Hang on a sec… I mentioned Nitrites, guess what, they are also toxic to your fish, I lied, your tank isn’t cycled. A second set of bacteria have to be established and will process the Nitrites by further oxidation into Nitrates. This bacteria like the original one will breed on all the hard porous surfaces of your tank.

Hard porous surfaces, some people like to think is a euphemism for filters. Whilst not wrong, it can also be the minute and miniscule pores on your gravel, the biofilm that forms on your rocks, the nooks and crannies of the microscopic nature that form on your driftwood, the surface of your plants even the bodies of your fish. Even without a filter, (which I wouldn’t attempt unless you were an expert), the bacteria will breed and multiply.

So we are left with these nitrates. Guess what, nitrates are non toxic! YAY! Sort of… Not really… No they really aren’t. Nitrates like all waste in the aquarium can build up to toxic levels and kill your fish. This is why weperform water changes. This is why people advocate the use of plants.

This is also where bioload comes in, if you have too many fish/too much waste breaking down/ or even too many pooping snails, the bacteria wont be able to keep up with the load, there simply isn’t enough of them andyour tank will quickly become an ammonia laden cess pit.

Before I continue, I would like to add, Nitrates are an excellent source of food for plants, they help the plant grow and provide a good way to remove the Nitrates from the water column.

Plants also will process Ammonia directly, so in conjunction with bacteria, will form an Ammonia fighting super team.

3. Oxygen and Carbon DioxideSo far we have learnt that Carbon Dioxide will cause an aquarium to become acidic and that plants process it

to form HCO3-. This is true. Plants however, also break up Carbon Dioxide molecules through a process known as Photosynthesis. This basically means that a plant will use energy from the sun (or the micro suns welike to call CFL’s, Fluoros, LED’s etc), to break up CO2 into C and O2. This is beneficial for both the plants andthe fish. The CO2 is toxic to fish at high concentrations. O2 is essential for life, this seems a pretty good trade off. It gets better though, the plants use the C (Carbon) that they have just scrubbed out of your water as a building block for their growth. The energy they get from photosynthesis allows them to develop Glucose and Cellulose Polymers out of the Carbon and to grow and make your aquarium beautiful.

Bioload features here as well, if the bioload on your tank is too high, the plants (or atmosphere in an unplanted tank) wont be able to keep up enough dissolved oxygen for your fish to be happy and they will slowly but surely get ill and die.

Also, plants at night time as I mentioned earlier no longer photosynthesise, instead the release CO2, just like fish and take in oxygen. Major problem if your tank is overstocked. Major problem if your tank is poorly buffered and can’t stand the PH changes due to the increase in CO2 concentrations.

Plants can’t just use carbon to fuel their growth however, (imagine a large growing piece of graphite in your aquarium, fun hey!), they rely on other nutrients, such as the aforementioned Nitrates and more. Which leads us to the next section!

4. Plant NutrientsOk, this is going to take a while and this is going to be huge. So ill put out some basics first.

Plants need a variety of nutrients to grow. The basic building blocks for plants are Nitrogen, Phosphorus, Potassium, Sulphur, Carbon and of course Oxygen. These are called the macronutrients. There are also dozens, and I do mean dozens, of micro nutrients that plants need to grow well. Heres a few, Ca, Mg, Mn, B, Fe, Na etc etc etc.

Ill do my best to explain.

Firstly, lets tackle algae. Algae is caused by imbalances of these nutrients in the water column. Algae is more specialized than plants are (mostly due to the fact that there are over 8000 species of true algaes alone), which means that basically, there is an algae for every imbalance. Algae will compete with plants for the same nutrients, and if the nutrients aren’t balanced, the algae will win. In a balanced aquarium, plants are better suited to outcompete algae, and you will be rewarded with a clean and clear tank. Now an example, If your tank has far too much bioavailable nitrogen floating around, you can bet that there will be an algae bloom that just loves to feed on nitrogen. Too much Silicates? The lovely brown diatom (which isn’t even an algae) will quickly colonize and invade your tank. Well, why is this a problem? The algae is incredibly unsightly for a start.Secondly, the algae will contribute to your bioload (although during the day it will bubble off O2, at night, just like plants, it is a good old fashioned CO2 factory). Plants help prevent imbalances in your water chemistry, as does frequent water changes, a healthy feeding routine and if necessary specific fertilization/carbon/lighting control.

OK. Onto Macronutrients.

You’re probably asking yourself, what is the best way to get Nitrogen for instance into the tank. Well, im not going to answer, there are dozens of ways and each tend to have their merits. I’ll explain 2.

Natural planted tanks are a popular option with fishkeepers, these type of tanks rely on a soil based substrateto provide some Macro and most Micro nutrients to the plants. The other source of nutrient input to the tank is fish food, which will contain again, most of the Macro nutrients that plants need. Decaying organic matter in the soil will provide carbon, nitrates, phosphates and sulphates to the plants. This accounts for most of the macro nutrients that a plant will need. This type of tank will eventually deplete the soil, but for years, it will be a plant growing haven. Once the soil is depleted it can be replaced, it isn’t particularly difficult. You can also supplement the soil with fertilizers, more on that next. Also, it is important not to forget that plants do need carbon to grow, the carbon can come from fish or it can be added, which again I will discuss next.

The second type of tank is for lack of a better description, a fertilized tank. Where you rely on additional fertilizers in addition to fish waste and sometimes a soil based substrate. The fertilizers that you add will supplythe plants with what they need in terms of macro and micro nutrients.

What type of fertilizer do I need?

Big question. There’s a lot of debate about this, so ill just keep it basic. You need to provide for the plants any nitrates, phosphates and sulphates that they wont get from the fish food. If you are purchasing fertilizer, this will be premixed. If not, ill explain what you can do briefly.

When you are supplying for instance, Phosphorous, to the plants, you don’t give them the pure elemental Phosphorous, this is a nasty substance that will start burning when reacted with water, not the kind of thing to be playing with. So you need to give it to the plants in a stable form. This stable form also has to be bioavailable and soluble in water. These bits of information give us everything we need to go on to start mixing up our own fertilizers. Sort of…

Stable forms of the macronutrients include, K+, PO4 3-, SO4 2-, NO3 -, CO2, just to name a few. Now, we still cant put these in the tank. They simply don’t exist (except CO2, that one does exist, causing climate

change and all that… yeah) . These first have to be produced from the elemental reactants. They are then reacted along a series of nasty steps and we arrive at our final product, Ionic Salts.

When adding macronutrients to the aquarium, they are added as ionic salts. The exact concentrations of each fertilizer I am not going to go into, if you aren’t capable of googling it, I wouldn’t suggest making your ownfertiliser. (I see aquagreen.com.au have an awesome range already mixed for you). But if you are capable of googling it, you will find recipes like PMDD and you will find measures of the optimal levels for the individual nutrients in the water column.

Some basic salts that are used for MacroNutrients and that are easily sourceable include:

KNO3- Source of Potassium and Nitrates, Ebay it. Also, don’t make the mistake I made and ask for it at Bunnings, it’s generally not sold at shops because it is an ingredient in explosives (this is why we cant have nice things) and they give you dirty looks whilst explaining. Also, if you cant get a hold of it, it isn’t the end of the world, the nitrogen cycle will supply you with the Nitrates and the Potassium is easily available elsewhere.

K2SO4 – Source of Sulphates and Potassium - Ebay it. Also sold at garden centres as sulphate of potash or some crafty deviation of that.

Phosphates – Most people don’t bother adding, fish poop, fish food and some rocks will do this for you, Phosphates are very, very rarely the limiting factor in plant growth

These are all bioavailable and soluble forms of the macronutrients, which essentially means they will go right where you want them, straight to the plants that need them the most (or to the algae that has become rampantin your tank).

Now, micronutrients. Micronutrients are a little more difficult to add. Without them, your plants will never grow,your tank is essentially a wonderland where all the little algal spores can frolic and play.

Most people will use a premixed micronutrient mix for most things, you are more than welcome to mix one yourself, but terrestrial plant keepers have done it for you, and they are pretty happy with the result.

The premixed micronutrient trace mix will consist of most of the trace/micronutrients you will need already combined into an ionic salt form. Pretty much ready to go into the aquarium. There are exceptions to this though.

Calcium for instance, has a different concentration and different uses in the aquarium than it does in the terrestrial environment. Calcium along with Magnesium make up the hardness of the water, there are a multitude of available compounds which will dose these two into the water. Infact, most people class Calcium and Magnesium as macronutrients, however I refrain from doing this as they do not make up a large portion dry plant mass, and instead are present mainly in the water as buffers.

CaCO3 – Crushed shell grit, crushed coral, Limestone all being good sources – Garden Supply, Pet Supply Shops

CaSO4 – Gypsum, good source of calcium – Garden Supply

MgSO4 – Magnesium Sulphate, a good source of magnesium and sulphur – Pharmacy, Woolies, Garden Supply

CaMg(CO3)2 – Dolomite, Good source of Magnesium and Calcium and Carbonates, dissolves slowly though-Garden Supply

The other trace nutrients that are vital for plant growth are Boron, Zinc, Copper, Iron, Molybdenum, Chloride (no not chlorine, chloride) and Manganese. These trace nutrients have varying levels of success in Ionic Salt Form, and it is often preferred to add them in a chelated form. You can chelate your own using various

Chelating agents, or you can buy them premixed. Chelating basically makes the nutrients more bioavailable and more stable, because certain metals, like Fe (Iron) will react with water and quickly become insoluble. TheChelate keeps them in suspension where they can be used by plants. It also reduces the toxicity of certain metal ions because they are no longer reactive and wont bond to sites they shouldn’t in your fishes body.

Often the limiting factor on aquatic plant growth is CO2, which means that your fish simply cant provide enough CO2 for the plants to use up all the nutrients and as such, the plants will be out competed by algae, this is a common case and will usually require reduction of nutrients, reduction of light or CO2 supplementation. This can take the form of Compressed CO2, DIY CO2 and dissolved organic carbon supplementation. Dissolved organic carbon supplementation are products like Seachem Flourish excel, Dino Spit (available from Aquagreen) and if you are into DIY, apparently Glutaraldehyde mixes can provide plants with carbon.

A couple of short things.

Mixing your own fertiliser is for people that have a better grasp of chemistry in the aquarium and have test kits that allow them to monitor the nutrient levels.

Dosing individual nutrients is even more difficult and should only be attempted by people that are certain theyknow what they are doing and are able to test the nutrient levels in the tank. There is a huge advantage in doing this though, as you can change fertilisation based on the nutrient deficiency symptoms/test results.

I don’t know the ideal levels for nutrients, these have to be looked up on the forum or on Google as they will vary wildly for different types of plants, and mostly because I simply cant remember the standardaccepted values (to be honest, not even sure if there are any accepted values).

And there it is, I think I got everything. I will be editing this in the future.

Hopefully this is helpful to someone. Also please, don’t copy this to other forums, if I like theforum enough I may post it there eventually, but it took me over 5 hours to write, so id like it to stay in the one place. And clearly, i did miss some parts, i will edit this in the future and make it a bit easier to read and a bit more informative.

Cheers,

Chris

Still needing more chemistry? Of course you are! Check out the article on Ammonia in the freshwater aquarium in the Members Articles Section of the the CDAS Web Site

paul

Rubber Stamp

A newbie's guide to getting your feet wet with social media via the CDAS Facebook page.

If you have avoided Facebook (as I did for severalyears), it may be time to reconsider. The CDASFacebook page is a great way to connect with fellowclub members and the broader aquarium-keepingcommunity and to find out what's happening atCDAS.

And you really don't have to tell everyone what youhad for dinner or post a “selfie” every few minutes.You don't have to even share any personalinformation at all if you don't want to – just start anordinary Facebook account (free), navigate to theCDAS Facebook page and “Like” the page.

To start your Facebook adventure, go towww.facebook.com. You'll be invited to start anaccount and fill in some basic information. You don'thave to put much here and you can elect not to shareyour information publicly (only with the “friends” youselect). Once you have done this, you have apersonal Facebook page which you can use (or notuse) as you like.

Use the search bar at the top of your page by typingin relevant terms – if you type “Canberra Aquarium”,CDAS's page will be in the drop-down list.

When you then visit CDAS on Facebook, you'll seea page that looks (something) like the picture on thenext page: Spend a few minutes getting familiar withthe layout. “Like” the page and feel free to leave amessage in the “Write something...” box to let othersknow you have joined.

If you select “Get notifications”, you'll receive anemail each time there's a new post on the site. That'snot always a good idea, especially when there are adozen new posts each day. It's probably better to justbookmark the page and visit regularly or wheneveryou feel like catching up.

You don't have to be a CDAS member to participatein the Facebook page discussion. Often, we'll receivecomments or questions from people in other parts ofthe world. If you find something you think otherswould like to know about, share it via the Facebookpage.

What Else is There on Facebook?

Once you have become comfortable using theCDAS Facebook page, there's a wide, wide world ofaquarium-related Facebook pages and groups toexplore. Two related pages you should certainly visitare the CDAS Breeders Award group page, managedby CDAS, and the Canberra & Surrounding AreasFish Keepers group page where you'll find a lot of theUsual Suspects hanging out and talking aboutfish-keeping in general. These are both good groupsto join.

Further afield, there are lots of Australian andinternational groups with Facebook pages. Use theFacebook search bar to find specialist pages ontopics such as killifish, catfish, African cichlids,

planted aquariums etc. Join those groups you'd liketo stay in touch with.

Most aquarium businesses also have Facebookpages. You can keep up to date with new fishshipments and equipment. Many offer specialdiscounts and competitions for their Facebookfollowers. Again, search for the name of the businessyou are interested in.

So, apart from teenagers sharing pictures of theirinappropriate behaviour, Facebook offers a widerange of legitimate and useful pages for anyoneinterested in aquarium keeping – or just aboutanything else.

A few tips for the new user – If you feeloverwhelmed or flooded with useless information, cutback and turn off notifications. You are fully in controlof the information flow so use that control to set apace and volume you are happy with. If you arehaving any trouble doing that, just ask and people willbe happy to share their own methods. Don't ever feelthat you have to respond to every post or question. Itis a large community and your involvement is entirelyoptional.

Other social media and web sites

There's a lot more to on-line aquarium sites thanFacebook. You may prefer the more sedate pace oftraditional websites like CDAS's own main site atwww.cdas.org.au. CDAS also hosts a members'forum at www.cdas.org.au/phpbb. If you prefer amore closed group, the forum may be for you.

CDAS also has a Twitter feed athttps://twitter.com/TheCDAS where we post shortmessages, links and updates. If you prefer Twitter toFacebook, subscribe to the feed and you'll be keptup-to-date.

Other social media sites are full of interestingaquarium information. You can search Youtube,Vimeo, Flickr, Google+, Tumblr or any of thehundreds of other social networking services foraquarium-related information.

Major aquarium societies also have their ownwebsites. The Australian and New Guinea FishAssociation (http://www.angfa.org.au) and theAmerican Killifish Association (http://aka.org/) are twoof my personal favorites. There are also purelyon-line communities operating vibrant communitiesthrough forums and blogs – check out AquariumLife(http://www.aquariumlife.com.au) – and especially theforums there – for an Australian example.

The CDAS Facebook Page – A bit complicated at first, but quickly learnable

These sites are also part of the CDAS social media family

Just a few of the manyFacebook groups on

specialist aquarium topics

On line and mailorder ordering of livestock can be a great way to get hold of fish, invertebrates or plants that are otherwise rarely available locally through shops, local breeders or CDAS auctions. There can also be some great bargains on-line. But before you load up your shopping cart and press “pay now”, it is worth taking a few moments to consider whether this is the right thing to do. There are a few traps for the unwary.

Do you have the right accommodation for what you are ordering?

Those new Peruvian Altum Angels may be very tempting at just $150 each, but where are you going to put them when they arrive? What about quarantine? Do you really want to mix them immediately with your rare Green Discus? Are your water conditions right for your new arrivals?Just as when you visit the aquarium shop or a CDAS auction, DON'T BUY ON IMPULSE. Plan ahead and think it through.

Is your supplier legal?

Lots of people will offer or advertise to send fish, invertebrates, aquarium plants or live food to you through the post or via courier. Apart from blatantly false and misleading claims (scams) the main thing you have to be alert to is overseas operators. IT IS ILLEGAL TO IMPORT LIVING THINGS INTO AUSTRALIA VIA MAIL. Importing fish, plants and other livestock into Australia is tightly regulated (thank goodness) and using a supplier outside of Australia, including through ebay, will not only mean you loose your money, it also means your order will either be destroyed by Customs or Quarantine authorities before you see it OR you may be prosecuted for a criminal offense if it does get through. Don't do it. Not even once. You may also findthat non-living aquarium items, like food, driftwood and some water treatments, are also illegal to import. Youare pretty safe with equipment purchases (but buyer beware, for lots of reasons).

Does your supplier know what they are doing?

Once you are sure you can properly house your purchases and your supplier is in Australia, the supplier's experience and practices are the things that make the most difference to the success of your order . Buying from an established and specialist mailorder business like Aquagreen (a CDAS sponsor) is very different frombuying from an individual on an on-line forum or from an interstate aquarium shop who says they can ship buthas no obvious track record. Fish and invertebrates do travel OK, most of the time – after all, 90% of what we see in aquarium shops has already traveled a long way to get there.But there are a few basic protocols that every seller should follow:

The livestock should be shipped as fast as possible after they areremoved from their normal accommodation. You don't want themsitting around in bags at a wholesaler's warehouse or at an airport forany longer than is absolutely necessary.

All good mailorder suppliers offer express shipping and try to get your

purchases to you within 24 to 36 hours. The good ones will starve the fish or inverts for 24 hours before they ship. This helps ensure there aren't excessive waste products accumulating in the bag during shipment. Most suppliers will use Australia Post's “live animal” service for shipping which guarantees priority handling through the transport chain and special treatment from package handlers. A few will use courier companies that they know and trust. Never order from anyone who puts their livestock in the normal post – even if it is “priority paid” or “registered post”. Not only is this a very bad thing for the livestock, it is also illegal.

Packing is just as important as the way things are sent.

A styrofoam container is mandatory and fish should be double bagged. Bags should normally contain only enough water to keep the fish comfortable – about a quarter full is good. The air (or pure oxygen) in the bag is as important as the water. The sytrofoam container should be tightly packed without putting too much pressure on the bags, by using half-inflated empty bags or newspaper or some other material to stop things moving around too much.

The shipper must include a heat pack or cold pack, depending on the season. These are special sachets of chemicals that help maintain a constant and appropriate temperature inside the box. DON'T LET ANYONE SHIP LIVESTOCK TO CANBERRA WITHOUT TEMPERATURE CONTROL. We livean an environment characterised by extremes of temperature and even a styrofoam box cannot keep its internal temperature stable for more than about 10 hours. Remember that the box will be in the hold of an aircraft for several hours and probably in the back of a truck for several more.

Finally, the box should be taped shut and labeled as “Live Fish”.

Buying Fish Retail and Arranging Shipping Yourself

I'm addicted to visiting aquarium shops wherever I travel. While I try to follow my own advice and avoid impulse buying (I even have a little mantra I recite before entering shop away from home -” don't buy fish, don't buy fish....”), there are times when, well, you know how it is. If I absolutely must buy livestock and I'm driving back to Canberra, I'll arrange to pick them up on the day I'm traveling home and tell the shop keeper what I plan to do, including how long it will take to get my purchases home. I'll ask them to use large bags, to double bag and also request a styrofoam box and lid. I'll purchase (or have with me) an aquarium thermometer so I can check the temperature in the box at points on my return journey. I'll put the box on the back seat of the car, covered with atowel to keep the sun off and keep the aircon set to the mid-20s.

If I'm flying, there are some airline rules to observe. QANTAS are pretty good about shipping live animals (I don't know about the other domestic airlines) but they can be a bit inconsistent about passengers traveling with a box of fish as normal luggage. The safest way is do a formal live animal shipment and to lodge a form with them the day before travel – it's on their website at http://www.qantas.com.au/qfreight/qfe/animal-booking/global/en/ and you can fill it in and lodge on-line.

Again, I'd pick up my purchases, with the box packed and taped securely, on my day of travel, leaving enough time to drop them off at the cargo depot. Usually, they'll travel on the same plane as you are booked on but sometimes you might need to pick them up from a later flight.

Most mailorder shippers will give you an estimated date and time of arrival, or, better still, a tracking number for your parcel. Most also ship early in the week to avoid live shipments sitting around over a weekend. It is a really good idea to have the package delivered to somewhere where it can be dealt with straight away – don't risk having live fish left at your front door until you get home from work or school.

If there's unlikely to someone home when the package is delivered, ask a neighbour or friend if they can take delivery and keep it inside out of the sun or cold. Or, even better, use the CDAS Forums to see if others want to participate in a “Group Buy” from your preferred supplier. Someone will need to volunteer to take delivery and at least float the bags in one of their tanks until you can pick up your order.

When you do get your fish home, inspect them in the bag to see that all have arrived alive. At this stage, I would normally test the temperature and pH of the water in the bag to see how big a difference the fish are likely to experience when they get into their new home. Take special care to acclimatise them to your tank water, using your normal method to equalise temperature and exchange water (or use the “bucket and drip” method to avoid introducing the transport water to your tanks).

Keep an eye on your new stock for a few hours to see that nothing is terribly wrong. If you are using a quarantine tank, give them at least a couple of weeks to show any signs of disease.

The Bucket and Drip Method of Acclimatising Fish

Usually, I'd float a bag of new fish in their new tank for twenty minutes before slowly exchanging about 30mls of water every few minutes to allow both temperature and pH to equalise. The alternative method is to empty thenew bag, water and fish, into abucket or container (1) and set up aslow drip of water from their newtank via a siphon (2). A piece ofairline tubing with a plastic valveallowing a drop per second is ideal.Once the depth of water in thebucket has doubled or tripled, youcan check temperature and pH ((3),net the fish into the new tank (4)and throw the water in the bucketaway. This method avoidsintroducing any of the shippingwater into your tank.

What happens when something goes wrong?

Fish can arrive dead or badly distressed, bags can burst or your parcel might get lost. You might also find you didn't get what you thought you ordered or the fish/plants are clearly not of “merchantable quality”. If there is something obviously wrong with your shipment, first take photos and then try to rescue what you can.Contact the supplier, by phone if possible, as soon as you can and explain the problem. If the box was damaged, the transport company or the supplier may give you a refund or replacement order. Some of the better suppliers will replace the order if you didn't contribute to the problem (say by leaving the box in the sun for half the day or just tipping the bag of fish into a new tank with acclimatisation). Others, sadly, take a less generous approach and will just say “bad luck” and point you to a disclaimer buried deep in their website. It's up to you whether you deal with these characters again. The fact is, some people, even some well-known aquarium businesses, don't do the whole quality-control and shipment thing very well at all and have a pretty caviler attitude to customer service once the dollars are in the till.

Plants Have Issues Too

While buying aquarium plants on-line doesn't have quite thesame set of issues you get with fish (I wouldn't insist on a heat/cold pack or overnight shipping, for instance) there's an extra dimension to consider – snails and algae. The best method I know for avoiding bringing in nasties on new plants is to give them two “dips” - one in a solution of Potassium Permanganate (“Condy's Crystals”) - at a few grains per litre, and one in dilute household bleach at about a cap-full in a litre of water (you can also use Hydrogen Peroxide instead of household bleach). Give the new plants about 10 minutes in each bath and then rinse thoroughly in tank or tap water at around 25 degrees. This is not 100% bug proof, but snails, snail eggs and most forms of algae will be killed. This protocol should probably by used on any aquarium plant you are introducing to your home set up – not just for those you get through the post.

Do your research before you order

Apart from making sure that what you are buying is appropriate for your tanks and skill level, there are few things you do to help ensure you are dealing with a good supplier. If their website has a feedback page, that's a good place to look for other customer's experiences. Secondly “google” the business name and see if there are other reviews on-line. Look specifically for recent comments about their shipment record. If you can't convince yourself that they are good people to deal with, ask for others' experiences on an on-line forum– such as the CDAS forum or AquariumLife. Read between the lines. People are reluctant to “bag” a business, particularly one that might be good in other areas. Some businesses also go out of their way to

prevent bad reviews being posted on-line.

Lastly, ask the supplier some questions directly. If it is not obvious from their catalogue or website, email or call them and ask about their shipment methods – do they use the official “live animal” method through Australia Post or a courier? Will you get a tracking number? How do they pack the box, do they use a heat/cold pad? What is their policy on DOA (Dead On Arrival)?

Some On-line Suppliers With a Good Track Record

I hesitate to recommend any business in this area because ownership, staff and policies can change at any time, but if I was asked right now to recommend on-line aquarium livestock suppliers, I'd give two of them fivestars:

Aquagreen – a CDAS sponsor in the Northern Territory. Dave Wilson, the owner, collects, breed and grows his own stock of (mostly) native fish and aquatic plants. He also carries a small range of “dry goods”. For me, Dave's shipments have never failed to arrive in great condition and he is a “model” shipper that I wish more suppliers would copy.

Coburg Aquarium – is a BIG retail aquarium shop in Melbourne and they do mailorder through their website.They have a good range and their prices are good and, more importantly, they pack and ship like professionals. They are always easy to deal with by phone or email too.

I would also recommend Liverpool Creek Aquariums for aquatic plants. While the shipping protocols for plants can be a bit more relaxed than those for animals, these guys do a good job.

There are several others that I know have a good reputation with other club members but which I haven't yet dealt with personally. These include Second Nature Aquarium in Orange NSW, who have a very tempting catalogue.

That's a pretty small list and I'm not going to put in writing what I think of a few others who have let me (and several dozen fish) down badly. Let's just say that if I'd done the research I've advocated above, I would never have ordered from them in the first place! If in doubt, ask on the CDAS forums.

40 So many marine fish come from real forces, shuffled a bit. (5,5) 44 A generic black band performs only this side of Wallace's line 45 Specifically, a Dutch crypto-authority sounds gone 46 Harry says her blue eyes gave her away as a generic fake muggle. 47 Common Botia is painted fool (5,5) 48 Give a shine to Dianne's poem with low wattage illuminator.(5,8,5) 49 Mixing nice soil will hold the tank together 51 Shaken, cavitated element seven absorbs and deodorises.(9,6) 53 Common submarine weapon, the American way, has backward facing point? (7,4)54 More specifically, articulate the name of a popular small livebearer 55 Biblical neotropicals generically have fins like leaves. 56 Math sin hue remix is bright green and sometimes tiny in foreground , but only generically speaking 57 Poor slum gal; tangy little things like shells

4 Super hot mixup nurtures, generically, from Burundi to Zanzibar9 The Skipper's boat but commonly small.12 Valerie, ill with a common virus, likes these better than eheims 13 Five must mix with specific quiet flag from Guyana. 19 Sounds like the badest little chameleon since Dario 20 Commonly, these little ephemerals sound like murderers. 24 I am law from old Nyassa 26 Precious but common and sounds a bit like a cold fish 27 Porcine? Moi? But I'm just a such a cute little version of Finn from Glee.(5,4) 28 Little catfish makes scary odor. 29 Mix rift roe for smallest food. 30 Scars unit delivers generic nasal bush 36 Sir Reeve Moss so mixed up, makes pure water by membrane magic (7,7) 38 Eye-spot commonly says no to mixed up orcas39 With all that shaking going on, it nets tetra (7,4)

Aquarium Cryptic #1

ACROSS

Here's something to keep you busy over the Xmas-New Year break.

23 Generically, the king of fish starts like music, asks why is it so and ends as a mafia leader.25 Common but periodically noble little tetra 30 Lol! A bag moll dropped Lana's first to make green water.(5,5) 31 Mixed up hideous corn for a group of Amazonian plants 32 Dorsal wit turns on its tail 33 Mix a snail liver for eel grass, twisty or straight 34 Confused airman ate sail for want of salty little latin shrimp (7,6) 35 Asian pugalists are generically sound between good and best 37 Commonly, you can find fish and writing instruments in nanos.41 favoritism towards Canberra's first uni, vegetable prospers on log 42 This mason's no nut! confused? Sure, but generically he's a Pisces with a graphite stylus 43 Dave's first, dropped by a drag queen, confused, sponsored CDAS. 50 Commonly an a-framed road vehicle for green, blue and other coloured siblings 52 Good golly miss, you're so common

1 Strangle a moan, but he's a pioneer for 'scapers 2 Ade in a big asian desert, became familiar with a bumble bee 3 A quacking little plant in the wrong place. 5 In short, put your filter on the outside rear, or a stove top. 6 On ya bike! Done first or tears before bedtime. 7 Mama I no cycle properly and now I have bad chemical! 8 Dark continental is squashed quite specifically 10 Treat Mr Nosy Emu, shaking well, most commonly by smearing lipstick over his face (5,4,5)11 Go nudge a native, but commonly more widespread. 14 Colourful tenor has aussie chocolate mustache!(14,6) 15 low eel tricycle for a common jaundiced shocking African(8,6) 16 Chop, chop! Taking off from Panama or glowing in the deep sea. 17 Rich drab Frenchman gave his name to a princess. 18 Roll the stone in Batavia to avoid common plant (4,4) 21 At least one of these is a cuckoo but most are just inverted - and have the same teeth. 22 Pet with so confused a disease is actually a parasite (5,4)

DOWN

Download a printable version at cdas.org.au/main/downloads/AquariumCryptic1.pdf

Here are two of our favorite tropical fish – the Clown Loach and the Dwarf Gourami. Can you colour them and answer the quiz questions about each one?

Where did the fish your aquarium come from? It's actually one of those questions that could have more than one right answer.

Maybe your fish came from an aquarium shop or a club auction – but where did they come from beforethat? Maybe from a fish breeder? Maybe from a business that brought them to Australia from a fishfarm in another country? But what about before that?

Every fish you keep in your aquarium, or those fishes' ancestors, come from a creek or a river or a lakeor a coral reef (if you have marine fish) somewhere in the world. This is true even for fancy fish, likethose bubble-eyed goldfish or veil-tailed guppies that have been bred for many years (or even centuries)in fish tanks and ponds and now don't look a lot like their great-great-great grand parents. Finding out where in the world your fish originally came from can be fun and interesting, but you might need a good book or the internet. You could go searching the world yourself, but you would need a hat and a lot of lunch money. Try not to get lost and look out for crocodiles!

Let's grab a map of the world (here's a nice one) and choose a few fish to start our research – we'll stick with some favorite freshwater tropical fish for now - the Zebrafish, the Angelfish and the Clown Loach . The only other thing we'll need is a good aquarium fish book or an encyclopedia. We'll start our research on-line by using Wikipedia.

Go to Wikipedia. In the top right of the page is a search box. Let's type “zebrafish” and click on the little search icon (the magnifying glass).

You should be taken directly to page about the zebrafish which has a first paragraph that starts:

“The zebrafish (Danio rerio) is a tropical freshwater fish belonging to the minnow family …...”

That's what we want! There really is only one type ofzebrafish and it's scientific name is Danio rerio. (If youneed to brush up on what scientific names are all about,you could read the article on this website called ScientificNames – or why fishkeepers sometimes sound like

they are from Mars – but not now! We're in the middle something important.)

The next sentence in that first Wikipedia paragraph also starts with something weneed to know for our research - “Native to the Himalayan region …..”. OK, now youmay already know where the “Himalayan region” is but let's say we don't know. Ifyou look at the “Contents” box on the Wikipedia page (just below that firstparagraph), you'll see that the second item in the list is called “Distribution” - thatshould tell us more about where the zebrafish comes from. Click on “Distribution”.

And right there at the start of the paragraph is what we've been hunting for:

“The zebrafish is native to the streams of the southeastern Himalayanregion, and is found in parts of India, Pakistan, Bangladesh, Nepal,and Burma.”

WooHoo! Check on your map where India is (its the triangle shaped country to the North-west of Australia. The “Himalayan region” runs right across the top of India and the countries next door – Pakistan to the west, Nepal to the north and Bangladesh and Burma to the east.

That was easy and now you know where zebrafish come from.

Let's try another one – Angelfish.

You can use the search box at the top of the zebrafish Wikipedia page. Just type in “angelfish” and click the icon to search. Do it now.

Oh dear! We haven't got an “Angelfish” page like we did for the zebrafish, we've got a long list of dot points that starts with the words “Angelfish may refer to:”

Why did that happen? Well, it's because the word “angelfish” is used for a few different different things, not just our freshwater aquarium angelfish. Look at this list. There are several fish called angelfish and even a “a short-lived

Scottish alternative rock band”, whatever that is.

I think we can be pretty sure that the angelfish we want is the first one on the list -“Freshwater angelfish, tropical cichlids of the genus Pterophyllum”. If you have anaquarium book handy, just check that the scientific name for our aquarium angelfishstarts with the word “Pterophyllum” (which is pronounced “terra-fill-um”, by theway). Click on “Pteraphyllum” anyway.

We get taken to a page for “Pteraphyllum” which starts with the words:

“Pterophyllum is a small genus of freshwater fish from the family Cichlidae known to most aquarists as "angelfish".”

OK, there's a few words there that might be new to you, but you get the idea. Whatthat sentence tells us is that there is group (“genus”) of cichlids (“family Cichlidae”)that fishkeepers call “angelfish”. Sounds like this is what we are looking for and thepicture over on the right side of the page certainly is the right fish. But the nextsentence is the one we want:

“All Pterophyllum species originate from the Amazon River, Orinoco River and Essequibo River basins in tropical SouthAmerica.“

Find South America on your map. Those rivers are REALLY BIG and fill up most of the northern half of South America.

So that's two fish we know about. Try the next one yourself – start by typing “clown loach” in the search box.

How did you go? Did you find out that the clown loach comes from Indonesia (which is just near Australia on your map). Were you able to find the two islands it is found on?

Congratulations! You are now a qualified junior “Biogeographer” - which is the name for a scientist who studies how animals and plants are spread around the world.

You could do a few more – try finding out where your own aquarium fish come from.

Maybe you can also find some books or other websites that talk about where fish come from. Or get a map and put some sticky notes on it and write down the names of fish that come from different countries. Fish biogeography can be a good topic for a school project too.

Did You Know?

• People have been keeping and studying fish for a long, long time. The scientific study of fish is called “Ichthyology” and a scientist who studies fish is an “Ichthyologist”.

• Many aquarium fish are still caught in the wild by fish collectors. Sometimes this can be a problem if they catch too many and don't leave enough to breed.

• A lot of fish are now bred and raised on fish farms. This industry is called “Ornamental Aquaculture”. Here's a diagram of all the steps involved.

• Many new species of fish are discovered every year by explorers.