1 inch of fish per 8 sq inches of water surface

[Erised]

I found a website that said a good rule to follow is: 1 inch of fish per 8 sq inches of water surface
Could someone confirm that this is an alright rule to follow?

If yes, then would that mean I'd be ok with 13 fish in my aquarium if the average size is 5" ?! (Tank is 80x40x50cm, meaning I have 496 sq inches of surface water, divided by 8 leaves me with 62" of fish! Each fish being an average of 5 inches, this would mean 13 fish. It seems like a bit much to me, then again ... I have heard overstocking is good. But this much?)

 

[freddyk]

No, that rule is sensless, like most rules of thumb.

Every tank should be evaluated individually based on the shape of the tank and the types of fish being kept. There is no rule that can work for every tank and every fish

There is are many reason why these rules of thumb are full of holes, here is one that would apply to you:
Your tank is 32" long, 16" deep and 500 sq in surface. A tank that is 42" long, and 12" deep is also 500 sq in. You can keep more cichlids in the longer tank then the shorter because length is the largest determining factor with cichlids, this is how territories are split up. 13 in a 42" tank? Absolutely. 13 in a 32" tank? Might be pushing it. All of this is also dependent on what cichlids are being kept. I cringe when anyone asks a generalized question about 'cichlids' because no answer can apply to all of them.

I have heard overstocking is good. But this much

This overstocking rule is mainly reserved for mbuna. Many cichlids need lots of space and freedom -most prefer it. As far as I'm concerned we should attempt to make the environment for our fish as natural as possible. In the case of mbuna, they actually do live in large, dense, and mixed groups in the wild, so we can happily duplicate this in the tank. They are quite content in very crowded conditions.
The determining factor for how many you keep is based not only on tank length, but also on 1)how often you upkeep your tank 2)How much filtration you are running on your tank 3)how aggressive your fish are (caeruleus can be kept very sparsly, demasoni must be kept very densly) and 4)what you prefer to see in the tank - it's your tank in the end.

 

[Erised]

That was a very informative post for someone as new as me, thanks a lot!!!
I am looking at mbuna's only right now, so the overstocking would be in place. I'm not quite sure what I'll end up with yet ... so for now I'll just browse, and in a couple of days I'll post a list to see what I can keep and in how many

Thanks again!