Can a frog and iguana live together?

i have a pet iguana about 2 feet long, and recently there have been a larg number of fruit flys in his cage,, even after i clean it they come back! i think they annoy him.. if i made the cage part water or added a bowl with part sand and water. would he try to eat it? if i got say a small fire bellied toad. or would he get too hot with the heating lamp?