multiple schools

[TomFromStLouis]

Our own Skeptical Aquarist states the following:

In all but the very largest tank, one school of fish will constantly break up the schooling patterns of a second school. "One school to an aquarium" is a good rule-of-thumb.

I did not know this. Is wetmanNY primarily saying this is so when the schooling fishes are of the same size? I thought people that throw a school of tetras in with their discus basically got two schools that stayed together pretty well. As well as discus ever school I suppose.

Anyway, I would appreciate anyone with experience who wants to elaborate on this to please do so. I am dreaming of my next tank, perhaps 180g +/-, and was hoping for two or more schools. Discus, tetras, SAEs, something like that.

So, does this one school rule mean that the broken up shoalers get stressed? Does it only apply if the fish are roughly the same size? Would a 180g planted tank be large enough for the 'rule' to not apply?

[GDominy]

Generally speaking, this is the case. I have been able to maintain two seperate schools of Rasbora's in the same tank, but "only" when there is something that is triggering a stress response (in this case it was a red tail black shark)

Tetra's tend to blend together (in my tanks anyway), but some barbs might be able to do the trick.

Another thing you could try is have two schools of fish with different behavior, say Tiger barbs and Harlequin rasbora's? That "may" work, and you would have very interesting interaction between them.

[RTR]

I am definitely in the one school per tank group. But if your tank is large enough and/or deep enough, you may be able to maintain separate schools at different depths. Whenever I've tried it I get interference.

If you haven't seen discus or angels school, the tank is too small.

[TomFromStLouis]

Interesting. That must be why my 9 angels don't school very often in my 75g - I knew I was pressing a bit on the stocking level. Still, the rummynose tetras are constantly together and while the angels sometimes shoal, the spawning thing has definitely kept up some segregation.

I also understand that wild angels school much more than domestics. And yes, I have seen discus school. It is quite a sight. Thanks.

[somefinnfishy]

I added 4 bosmani rainbows to my congo tetra tank 90g they school with the congo's :rolleyes:

[Cearbhaill]

I have a group of Cardinal Tetras, a group of Harlequin Rasboras, and a group of Diamond Tetras in a 90g tank. I won't call them schools because they don't school (or shoal) at all. The tank has become so comfortable for them that they just poke around in the weeds all day. Without a threat of any kind I guess they have no need to stick so closely together.
I am planning on adding Discus to this tank by the end of the year, but do not have my heart set on schooling behaviors- my home is just too tranquil!

[JP457]

I had a 45 gallon with a school of neons and a school of Marbled hatchets. They had 2 separate schools but the neons were always bottom/middle and the hatchets were always top/middle.

[RCA]

Originally posted by TomFromStLouis
Interesting. That must be why my 9 angels don't school very often in my 75g

For the most part, I think angels school only when young. They can get feisty when mature, and pair up, leaving the unlucky males by themselves.

I find that my cardinal tetras also school more when they know the tank light is about to be turned off (I have a timer). It's amazing that they can seem to sense it, and form a school as they get frightened.

[Tim Bo]

My experiences have also shown me that in general mulitple schools don't always work like I hoped. Those times where the fish did school was when they were frightened or worried about a threatening presence in the tank. This would separate them into their own groups and make them school free of each other. One large LFS, Zoo City, where I live has an 800 gallon full of different (predominantly tetras) mixed with large cichs and they seem to school fairly well when I see them. Love that tank.

[RTR]

Very few fish have long pair-bonding in the wild. In a large tank with sizeable open spaces between areas of cover, you will see mature Angels or Discus schooling.