The tadpoles should be raised separately from the adult frogs. I raise tadpoles in a 2 gallon tank. The tank has an air powered "small world" filter from Malwart. I have a valve on the pump so I can turn it way down.
There are plants in the tank to encourage the growth of infusoria (a micro organism that the tadpoles will eat during the firs stage of their development). I use Elodea, Water Sprite, and Java Moss in my tank.
After the tadpoles first hatch I add a drop or two of liqui-fry #1 2 times a day to help the infusoria to grow. The tadpoles will eat infusoria for the first few days.
When they are a bit larger I begin feeding baby brine shrimp and micro-worms. I also had success feeding crushed "frog and tadpole bites" During metamorphous I fed frozen and live daphnia, and live tubifex worms.
The tank is unheated, and is about 24 C in the day, dropping to about 23 C at night.
Don't use gravel in the tadpole tank. The tadpoles swim into the gaps between the gravel and become trapped.
After metamorphous is complete, continue to house the baby frogs away from the adult frogs until they are too large to be eaten.