fry are very sensitive. any ammonia at all could be detrimental to them.
It takes time for ammonia to build up to measurable levels and even longer
to get to a "spike". You are doing large water changes which keeps diluting
what small amounts of ammonia the fry are producing so you are not seeing
the ammonia at high levels. All of the nitrifying bacteria live in the
filter and the gravel and other surfaces in the tank. It is not free
floating, that is why I say using cycled water doesn't do any good. You
can take some cycled filter material and put in the new filter to speed up
the cycle though.

as to your fish question, the mother would most likely eat the other fry in
the tank if you were to put her in there. But there is no telling. But if
you put her in the fry tank you probably will see that it is not cycled
because of the extreme load a fish of that size will put on such a small
tank, if you could even fit her in ;op
--

Margolis
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