he said it WAS a bullfrog. That leads me to beleive it has changed into something new? Maybe a witch turned it into a toad LOL. Bullfrogs will eat anything they can get in their mouth. Mice, small turtles, other frogs, small lizards and snakes, fish, bugs....you name it, they will likely eat it.
A better description would have helped. Like when you say it is a dark color....ummm dark what color? Green, Brown, Black, Purple?
Superworms, wax worms and millworms and 2 inch feeder fish (shiners or shad) would be a good base diet. An occasional fuzzy mouse would be a nice treat. Keep the water clean and don't put him in fresh tap water. Frogs absorb every contaminate they come in contact with right through their skin and into their delicate system...this is why as a pond, lake or stream becomes polluted, the first thing to dissapear are the frogs. I use this for a gauge to judge if I will eat fish from a certain body of water. If I don't see or hear frogs...I don't eat the fish.
Also make sure you have a dry area in the tank...it can be damp but the frog needs a place to get out of the water from time to time...Live plants in this area give hide spots and help keep the air clean and fresh.
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