I hate those kits! Its perfectly understandable to be mislead by the marketing. This is a reliable website all about the care of leopard frogs, which might help. Amphibian Care >> Leopard Frog (Rana pipiens and R. utricularia) Care . Twenty gallons is plenty for two frogs, but I wouldn't recommend raising tadpoles in the same tank as the adult, because the adult might eat it. You could take the risk, as long as you monitored the size of the frog and make sure it can't, or doesn't think, it can fit the little taddie in its mouth. Another important factor for the leopard frog tank, since it has to be 50% water, an in-tank filter. Tetra makes great and inexpensive filters, so that might be an investment so you don't have to change the water as much. Hope that helps!