That's cool! I've been thinking about getting a tarantula or a mantid eventually. You're right, one African Bullfrog isn't too big a dea, I just felt I should say something you since you bought three tadpoles initially. Speaking of them, I'm glad you're going to get a confirmed ID before deciding what to do with the frogs.
In any case, I really like my own ABF and would recommend them wholeheartedly. They're cool frogs, if a little inactive.