20 - 25 gallon (UK) aquariums/tanks - what/how many fish have you got in yours (against the rules?)?

Question

What I mean by 'against the rules' is, time and again we are told to stick to a certain limit of fish per tank, which is fair enough, but as with all things in life there must be people successfully breaking the rules without any problems.

Tell me your experiences, those of you who have more than they apparently really should.

I have a 22 gallon tank with two goldfish, I get told constantly not to put anything else in there at all - surely a few little fellas wouldn't hurt that much???

Answer 1

I think your question actually addresses two different issues.

The obvious one is overstocking, at least according to the "one inch per gallon" myth. I've had many tanks that people who follow that "rule" would consider overstocked, but they don't take into account the influence of filtration, frequent water changes and cleaning, use of plants in the tank, and so many other things that make the rule bogus.

Because I get away with this, should everyone overstock their tank? Probably not. People new to fishkeeping probably don't have enough experience with cycling, aggression/territoriality issures, don't test their water, or don't pick up on behavioral cues as to when a problem is starting until it's too late. People in fish/pet stores, unless they know you, are better off suggesting that you understock your tank for the overall benefit of your fish.

And for fish like goldfish, plecos, cichlids and others that are big waste producers, more fish may lead to water quality problems that much sooner with additional wastes in the tank, so there's even more reason to limit the number of fish.

The other issue that is less obvious is that of keeping a fish in too small of a tank. You don't mention what type of goldfish you have, but look at the difference in size between a common (single-tailed variety) and fancy (double-tailed variety). Two orandas may be perfectly at home, but two comets may have little room in your tank. If the adult size of a fish is larger than a tank can accommodate, the fish might live, but have its growth stunted - this means the body size stops growing, but internal organs can continue to grow and press against each other until their function is inhibited, leading to a premature death of the fish.

I've worked in retail fish sales, answer fairly frequently in this forum, and have been keeping fish myself (sometimes in pretty limited space) for over 30 years, so I see both sides of the "how many fish can I have in this tank" problem. And a lot just boils down to experience and committment of the individual keeper as to how far the "rules" can, or should be pushed.

Answer 2

The rule of thumb is one inch of fish per gallon

Answer 3

You are at the max of the tank. I keep tetras, a betta and a few rasboras in mine. Its very colourful =)

Answer 4

have same size tank ...but only one fish... its a six foot long cat fish!