Re: [RML] rainbowfish diet/ASTAXANTHIN

Bruce Hansen (bhansen at
Sat, 19 Sep 1998 08:33:57 +1000


I guess there are a lot of reasons why rainbowfish usually don't get too
large in the wild but I think predation would be the major one. The lomger
they are "out there" the more chance they have of not staying away from a

Also I guess there are selective predators for each size range of food items
as well as each habitat. Some predators will ignore expending the energy of
the chase on a small item but actively pursue a more meaty one and only go
after the tiny ones if they are really hungry.

When we keep them in tanks we protect them from predators and supply them
with food that they don't have to chase much - just open the mouth and suck
it in


Bruce Hansen, A.N.G.F.A., Advancing Australian Aquatics.

Bruce Hansen, ANGFA, caring for our aquatic ecosystems.

Please visit us at

-----Original Message-----
From: Stephen Boulet-CSB046 <Stephen_Boulet-CSB046 at>
To: rainbowfish at <rainbowfish at>
Date: Saturday, 19 September 1998 0:27
Subject: RE: [RML] rainbowfish diet/ASTAXANTHIN

>>At first I would answer - yes! However water quality and other
>>environmental factors seem to have a significant influence too. But
>>in general wild caught juveniles are better coloured than similar
>>sized ones raised indoors in aquaria
>Another thought: I understand that wild fish don't generally get as big as
>aquarium fish because of the rigors of actually working for a living. So
>maybe wild juveniles of the same size as aquarium raised juveniles are
>actually older, more sexually mature fish?
>-- Stephen
>Grayslake, IL USA