I don't know how big your critter keeper is, but the ones I've seen are about a gallon. Fry need really clean water, so regular partial water changes are important. If you can put a little bit of your substrate from the main tank in the little tank, that might help. Check out what kind of fry food you can get a hold of - they'll be too small to eat anything larger than a fine grain of sand.
I know - it's nearly impossible for me to see babies and just leave them be. It certainly helps assist the
MTS.
