DS wants a fishtank - advice please.

[WhoWhoWhoWho]

We have a large petshop near our house and DS is always looking longingly at the fish and tanks in there.

If I were to get him a tank, how do I know how many fish it can 'house'? Is there a rule of thumb size wise as to how many fish fit in a certain size tank? I would only be getting a cold water tank set up not a tropical fish set up. Does that mean goldfish only?

Do the filters cost much to run (electricity wise)? I'm assuming it is switched on all the time? I want to be aware of all long term costs before I cave say yes.

I know I could ask all of these questions in the shop but then DS would hear and I don't want him to step up his pleas.

you need the biggest tank you can afford. if you want to keep goldfish then bear in mine they will grow up to around 20cm or more so need a very big tank, and they produce a LOT of waste

there are other coldwater fish that aren't as big though, minnows are quite pretty.
most fish like to be kept in a group so you'd want at least 6.

the smaller the tank, the harder it is to keep clean IMO, and I would get at least a 60 litre tank for 6 minnows, but obviously, the bigger it is the better it is for the fish cos they will like lots of space to swim around.

i have no idea how much filters cost to run, but i don't think it's masses, we haven't noticed a particular jump in our bill since having our 2 tropical tanks set up

also, read up on fishless cycling!

I have a 60 litre biorb tank which can hold 3 fish, the filters are around 7 pound and last around 4 mths. It has bubbles going up the middle and a light it looks lovely when lit up. Electricity wise i havent noticed it costing anymore, it runs on a 12v pump hope that helps.

That's reassuring that you haven't noticed a jump in your bills.

I have not paid much attention to the tank sizes when we've been looking, next time we go in I will weigh them up size wise and price wise and see what we can buy up to. Obviously if I can't afford a 60l one I'd rather not bother than have fish in a too small tank!

Do minnows grow big or do they stay the same size? Probably a silly question .

Will look up fishless cycling too. Thanks for your advice I really appreciate it. smile]

I've seen those tanks spicyorange they do look nice.

I definitely need to continue with some covert research!

Biorbs do look good but they are not designed with fish in mind, the tiny surface area is not good for gas exchange and the filters aren't very good. You can get a much better tank and filter for less money.

As TIY has said, minnows are a great fish to start with, they are easy to look after and they don't get very big. You can keep a shoal of 6-8 in a 60 litre tank. I wouldn't recommend a smaller tank than that if you're just starting out, smaller tanks are quite hard to maintain because the water quality can change so quickly.

And yes yes yes to fishless cycling. This explains it well.

You do need to keep filters switched on all the time but if you have a coldwater tank then that keeps costs down. You could just use one lightbulb as well. You can still have real plants with one lightbulb but you need to choose ones that are happy with low lighting. Fish love real plants and they look great if you choose easy to keep ones like java fern and crypts.