My frogs LOVE sake cups to breed in! I put little black sake cups in the tanks before I could get coco-huts, and they seem to prefer them to the coco-hut/petri dish, the various natural pods, and plants I have in there. In fact even with all of these other "ideal" mating spots, as soon as I removed the tadpoles, cleaned and replaced the cup they laid another clutch of 7 eggs in the following 2 hours! My azueus and my auratus seem to prefer the sake cups. Soon I am going to have to more tadpoles then I know what to do with (If all goes well).