I captured a bunch of tiny tadpoles today and put them in a big tub with some pond water. What do I feed these guys? I ground up koi food and sprinkled that in and they seem to eat it. Obviously they can't be in our ponds now because my koi would eat them in a second. But I would like to grow them big enough to have them live in my ponds and put the others back in the place they came from.