John,
I always raise my fry either with an undergravel filter or a box filter with
the lid removed. The reason I remove the lid is because I have found that
fry can get trapped in the filter. With the lid removed they can swim in
and out. Also you will find that the fry will pick small infusorians from
the filter wool. Sponge filters are also OK. However, I have always had
bad results raising fry in tank without any biological filtration. If you
want to raise all the fry they usually require "heavy" feeding and this can
lead to water problems if you have no biological filtration. Its a good idea
to add a few mystery snails to the aquarium to eat any left-over foods. The
snail droppings are also a source for creating extra infusorians.
I guess it depends also on the number of fry you are trying to raise and the
size of the aquarium. For instance, if you have a 100 litre tank and only 10
fry then obviously you are not going to get water problems. But on the other
hand if you have a 50 litre tank and trying to raise 200 fry then you will
probably have problems.
Adrian.
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Adrian R. Tappin
atappin at ecn.net.au
http://www.ecn.net.au/~atappin/home.htm
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