Thanks so much for the advice! Frogs are still healthy and active...I think I'm starting to get the hang of the fruit flies. I started some cultures a week ago and now there are visible larvae(?) - looking like little grains of rice?

I read through the links - they were really helpful, thank you. One other question -- how long do I need to keep adult flies in the cultures? Do I keep all the adults in there to keep reproducing, or do you usually feed out the adults once the larvae start appearing? Not sure if I need to leave them all in there to keep reproducing. I have four different cultures going, started a week apart.