We used a 600 gallon water trough as a kid pool this summer. We had drained most of the tank but left a a couple inches that were below the drain plug. When it came time to move the tank the boy realized it was full of tadpoles. I had them catch some of them and relocated then to boys aquarium. They fed them fish food flakes. This morning they saw a frog stuck to the glass above the water line. So far we have turned two little tree frog loose this mornin to live on there own. Im sure not all of the tadpoles are tree frogs but as they loose there tails they will all be released. I will add photos as they come along.