Its not an exact since thats for sure. I've spent about 3 months getting the weight of my azureus under control, they were huge. For young frogs you want food around all of the time, but not tons either. The banana thing does work well, and gives you a good idea what is still in the tank. When the lights go out at night the ff's will come from everywhere to the banana.
I think I at least am starting to figure out the amounts each of my frogs need, and it is not really that much. A few ff's a day. I was really overfeeding them, so its a matter of what works for you and your tank. I can say there are a lot less escapes when they are fed properly.
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Kyle
Dart Links - still a work in progress
1.2.0 D. leucomelas
1.1.0 D. azureus
1.0.1 D. imitators
0.0.2 D. ventrimaculatus