I would like to place a scavenger in my frog tank. It would make my ecosystem nearly perfect. I really dislike the snails and slugs in there. They eat the leftovers out of the dish, but then occasionally nibble the plants too. I know hissing cockroaches are supposedly scavengers, and not predators. I know they eat decaying plant and animal matter, but I'm not sure if its wise to keep them with a dart frog. They may not eat the frog, but I wonder if the big bug could disturb a frog as it might compete for the frogs hiding spots. We're talking tinctorius here, mostly groundwelling.