Tropical Fish Forums

[submariner]

I was wondering do fish freshwater or saltwater fish school in an aquarium?
I have never seen that, someone told me they do I don't think so but I don't know fish well

submariner

[Topper]

The terminology can be a bit confusing with this and my explanation might be a bit off.

A school of fish is usually described as a large group of the same (or similar) species. When fish "school" they move together as one - changing direction in unison. When disturbed by a predator or obstacle they will always reform into the group. They act this way mostly for protection from predators but also to find food, spawn and possibly to cut down on drag during migration (like geese). This behavior requires a lot of space and very few home aquariums are big enough. You can see fish schooling at a public aquarium.

What we see with groups of fish in the hobby is called shoaling. It is technically a school of fish but their behavior is more of a loose social group. They will move in unison for a short time, but break up quickly. There is no real formation as you can see in the wild (or public aquariums) as space does not allow it. When they swim together in unison it is usually as a response to a larger fish coming into their vicinity or to follow a single fish that may have found food. Tetras and rasboras exhibit this behavior quite often.

So the short of it is that you need a very big tank to see a school of fish school together.
_________________
You're gonna need a bigger boat...

[UncleWillie]

Excellent explanation, Topper.
Schooling is what you see with a lot pf pelagic (open-water) fish like sardines, anchovies, herring and shad. Like Topper said, they move as one (school) and is used as a way to confuse predators. You may have noticed that a lot fo these fish (shads, some open water Cyprinids) will have a very pronounce and dark stripe or 'eye' spot (near head or tail). The fish within the school use these spots or stripes to 'lock-on' to one another. A combination of staring at that spot and lateral line senses allo them to pick up on the tiniest of movements and act as one.

Whoa - that turned out to be too long...

Anyway, most other Cyprinids or Characins tend to be shoaling fishes. The form loose groups for various reasons (social, reproduction, predator avoidance - the more fish around you, the more eyes are used to spot danger!). Anyway - I got carried away.

I think there are a few other posts around here talking about shoaling / schooling in aquaria. I will try to dig that up...

[UncleWillie]

Oh! Here it is. A thread a hair over two years ago. It's amazing what you learn in 2 years - I feel a bit more educated now than I did then

http://www.aquahobby.com/board/viewtopic.php?t=54466

[Brenda24]

don't forget the harlequin rasbora