Stocking a Tank
How to Stock a Tank
So you've put your tank through The Nitrogen Cycle and you're all ready to add fish to your tank! You go to the pet shop, excited and wallet in hand, and you're confronted with rows and rows of tanks of fish, and you feel like you've hit a wall. What do you get? Where do you start? This aquatic shop worker is maybe a little too keen to get you to part with your cash. And what on earth is THAT?
Please note this article is based on a freshwater tank.
This handy guide will hopefully get you well on your way to having a tank that works long-term with everyone staying happy and healthy and no nasty surprises!
You can read our volume-based stocking guides here:
And our other guides here:
Where do I start?
First up, know your tank. Yes its a big glass box full of water, but you need to know more than that. In order to know what fish will thrive in your tank, you need to really know your set up.
- Know your volume! If you don't know the volume of your tank you can't even begin to stock it properly. Do take into account water displacement, that's the amount of space taken up by substrate (which shouldn't really be deeper than 5.1cm (2")) and your decor.
- How is the filtration? Is it strong with a good current, or is it gentle? Is your tank over filtered with a filter rated for a larger volume than its set to? A tank with a strong current isn't going to be suitable for shyer slow moving fish like Angelfish or Bettas. An over filtered tank will better cope with messy fish like Plecos, but over filtering often also skips hand in hand with a strong current, this can be changed by using a spray bar.
- Is it heated? If you plan on keeping about 98% of those super dooper fish you see in the store, you need a heater installed. Make sure its the right wattage for your tank or you risk it blowing on you if the wattage is too low and the heater is struggling.
- What is your water chemistry? Now your tank has cycled you can find out what the stable water chemistry is in your tank. Now is the time to test pH, kH and gH. Knowing these means you can buy fish that thrive in your water and you don't need to fuss around trying to alter it for their needs. Leave altering water chemistry for the experts as its diffcult to do properly, concentrate on fish that love what you already have.
Right I know all that, can I buy a fish now?
Technically yes, you can buy whatever fish you want, but if you want it thrive you have to know what the fish actually is and what it needs. Don't be afraid to be an aquatic shop tourist, take a pen and paper (or use your smart phone) and write down names of fish you like, come home and research them on the wonder that is the internet. Don't rely on one website, cross check all the information as everyone has a different opinion.
Next plan your tank. This is the FUN part of new aquariums and why most aquarists suffer from MTS (multiple tank syndrome).
Here are some ideas on how to plan your tank.
The Candy Store Tank
The most common of the beginner aquariums. Its the one that looks exactly how it happened, the owner went into the shop like a kid in a candy store. They got that one and that one and ooo look at the shiny one I'll have two of those, and that one and that one. This is how NOT to stock a tank! A Candy Store Tank rarely lasts more than a month or two without fish dying/vanishing.
The Basic Community Tank
The basic tank follows a simple pattern, bottom dweller(s), mid/top dwelling shoaling fish and a "centrepiece". It has to be done carefully so you don't end up with a centrepiece that eats the shoaling fish, or shoaling fish that pull all the fins off the centrepiece, or a bottom dweller who maybe works perfectly for months until one morning everyone else has vanished and the bottom dweller has a ominous looking fat belly!
There's nothing massively wrong with this set up but a lot of thought has to be put into it. The most well known "centrepiece" is the Angelfish. And they often work well, but it must not be forgotten that the Angelfish is NOT angelic. Its a Cichlid and an ambush predator viewing small shoaling fish like the Neon Tetra as lunch. In a bonded male/female pair of Angelfish, if they decide to breed they'll turn into terrors!
The second most common is the Gourami. There are dozens of species of Gourami and some work well, some definitely do not, and the males are not fans of other males either!
So if you decide to go for the typical "basic" tank, don't assume everything is compatible, it's really not and this basic set up needs just as much research done as any other.
An example of "safe" bet would be something like this for a tank no smaller than 114 Litres (30 US G.) without a very strong current:
The Moonlights get the top area of the tank to swim around in. The Rummynoses are a bit too big to be eaten and are mid-bottom dwelling so they will stay out their way. Corydoras are lovers not haters. And, best of all, they all like a similar water chemistry.
This is, quite honestly, the best kind of aquarium you can set up as, done properly, the fish will compliment one another, like similar things like water chemistry, and make far more of a talking point.
Biotope means you will have a section of a waterway somewhere in the world, in your house, such as a mountain stream in China or a tributary of the Amazon. This kind of tank is the most fun to research and you not only have to know the species but also get to scout around shops and talk to the store to find out if the species you like you can actually get.
A biotope doesn't have to be huge, it doesn't even need to feature fish and could be, say, a slice of an Asian swamp with the correct plants and invertebrates. It also doesn't need to be entirely peaceful if you like your fish with attitude. You can get very geeky setting up your biotope!
There is one biotope that reins supreme over all and was there long before biotopes became the "in" thing to have, and that's the Lake Malawi Mbuna Cichlid set up. Everyone knows this one, its full of rocks, no plants, and lots of colourful Cichlids. But not even this set up is simple. The most successful ones are over 208 Litres (55 US G.) and a lot of research has to be done into the Cichlids too as they are not all compatible and you have to match temperaments to avoid fish being bullied to an early grave. It doesn't have to be all Cichlid either, some species of Synodontis Catfish can work in these set ups.
The world is, almost literally, your oyster.
Less is More
Don't forget that just because you have a tank means you have to cram it with fish. A happy stocking may not be a full stocking. Some fish don't really like the company of others, they like their personal space, their territories. Territorial Cichlids like Oscars are prime examples of this rule. Some of the most stunning tanks can be created with landscaping, or rather aquascaping, with minimal fish or inverts included, i.e. carefully arranged wood or rocks with just one shoal of small fish like Harlequin Rasboras.
If you want to do some research on species that could work your tank use some of these sites as well as our guides above: