Add a small block of tree fern fiber in your springtail culture. Springtails tend to gather in the block which can be easily transferred to the tank for feeding. Place a container with beer, but put some kind of a mesh screen so that the frogs won't fall in. Another good way to sex younger, juvenile frogs is by looking at their snouts. Toepads are only good on subadult frogs and adults, so using the snout methods is better for juveniles.
Males tend to have closer eye separation than female, making their snouts narrower.
Females, on the other hand have a wider eye separation, making their snouts wider. Mike Castiglione Have a fruitfly rotation schedule to avoid exhausting a batch of fruitfly cultures. This way, you give ample time for the flies in the first group to produce more flies. I've attempted this before and it resulted to frog deaths, resulting from stress. The frogs stopped eating and just wasted away.