How to feed Tree Frogs Fruit Flies in large terrarium

[BlueKiwiOca]

Fruit flies can climb glass easily, so the bowl method only works for crickets, roaches and grasshoppers. For my froglets, I feed them in a critter keeper with a sheet of muslin between the lid and the base to keep the flies from making a run for it. I have tried feeding in the terrarium, but the fruit flies can fit between the gaps in the glass of mine (I have an Exo-Terra).