Hello Jennifer,
if you wish to see a shoal of rainbowfish, the first step is to give
them the necessary space.
For example: My M. praecox (6cm) like to form a shoal in the afternoon
an early evening hours. The group of 10 fishes take up an area with a
diameter of 30 - 50cm. If you want to see this, the minimum length of
the tank should be 100 to 120cm. This is about 20 times the length of
the fish.
I think for other rainbows the proportions are similar.
You can keep and breed the rainbows in small tanks, but if you want to
get a very little impression of their natural behavior, like the
building of territorys (in the morning) or shoals later in the day
you must give them space.
Glossolepis incisus 15cm--> 300cm tank
Melanotaenia boesemani 12 --> 240 cm tank
Melanotaenia goldiei 14 cm --> 280 cm tank
are available ( at least for members of the IRG ;-))).
M. boesemani you should get from your local dealer.
Kind regards from Cologne,
Michael
...IRG 275
michael.m.haas at netcologne.de