Fish per 75 Gallon?

FishNewbie4Now

How many fish should I have in a 75 Gallon tank?

Little-Fizz

That would really depend on what type of fish you were planning on having in that 75 gallon tank.

If you go for small fish, a lot.

Bigger fish, not so much.

To give you a basic idea, one gallon of water per inch of full grown fish. But this is pushing it, and it's only to give you a rough idea. So I wouldn't be putting 75 one inch fish in there!

You should go to your fish store and make a list of fish you like then come back and we could give you a better idea on stocking your tank.

Have you looked into cycling your tank before you add the fish?

Tyyrlym

The inch rule isn't universal by any means, some fish are far messier than others. Goldfish are a prime example, they're much larger inch for inch, than most fish and consequently make much more waste. Also it depends on filtration. You can keep larger groups of fish in a tank if you're willing to really go to town on filtration and do lots of water changes. My LFS has a 29 gallon tank heavily planted and with ~50 inches of fish in it. They also have a sump on it that would be overkill on my 55 gallon tank.

Oh, and remember, it's adult inches of fish. Most fish you see in a store are juveniles. Plan based off adult lengths.

Little-Fizz

Meh, I would never put 50 inches of fish in a 29 gallon. Even if I had the best filter in the world. Sounds crowded and not somewhere I would want to live.

But yes, your right, I forgot about the fact that different fish have different bio loads.

Tyyrlym

Not claiming its a great idea, but I've seen it done.

iamntbatman

Yep...it all depends on the fish. I would have no problem putting a school of 75 neons in a 75 gallon tank. However, I would not put five full grown oscars in a 75 gallon. The "inch of fish per gallon" rule is pretty useless most of the time. If there was a rule, a better one would be volume of fish per gallon, although that's still not accurate as some fish are just plain messier than others.

FishNewbie4Now

2 Oscars, a Jack Dempsey, and a Green Terror Cichlid. They are getting along fine for now but I hear they will get more agressive as they grow and get used to the tank. I have another 75 Gallon if I need it, I was just wondering if that would be too many fish for one 75 Gallon Tank. I have a great filter, one of the biggest I've seen, I had it on a community tank but it was too powerful for some of the little fish, so I put it on the Oscar tank. I have a few other filters but it doesn't seem like I need them on the tank yet.

iamntbatman

You might be able to get away with that although even with the best filtration possible, you're still going to have to do regular big water changes to keep the nitrates down once those fish are full grown. Also, be prepared to move any of those fish if you get aggression problems down the road.

thespiff

You're probably in for quite a war zone there. I wish you luck. At least one of those guys will probably get killed before they are full grown. Probably more. And as they grow it will quickly become obvious that a 75 isn't big enough for those 4, even if they do get along. My brother has two Oscars, a tiger and an albino, each in its own 30 gal, and both of them are too big for their homes. In a 75 gal, split 4 ways, they essentially will each have about 20 gal worth of territory apiece which is far too little for a large cichlid.

Maybe you should think about narrowing down to one species, getting 2 females and a male, hoping that the male pairs up with someone, then removing the extra female. There are other fish which are compatible with big cichlids, so the tank doesn't need to look empty. Synodontis catfish or Plecos come to mind. They should be able to coexist with a large mated pair of cichlids, and will occupy different areas of the tank.

FishNewbie4Now

I split them up, I now have the 2 oscars in their own 75 Gallon Tank, and the Jack Dempsey is with the Green Terror in their own 75 Gallon tank. Could I put anymore Oscar's in with the 2 I already have or is two of them the limit?