good luck with these guys, i got a batch of 5 or 6 pacific treefrogs(not actually a treefrog through) about 2yrs ago and managed to get 2 of them to leave the water, one disappeared after about 2mo but i still have my female who lives in a 20g now, they're awesome frogs.
When both species of frogs are small tadpoles, I'll feed them boiled pieces of lettuce and when the Bullfrogs start getting bigger than the treefrogs, I'll seperate them in 2 ten gallon tanks.
I will then put about 6-8 treefrogs in 1 ten gallon and feed them small crickets, and I will use the other ten gallon to put in one bullfrog adult and feed him/her feeder goldfish that have been put out of water. Seeing a beached, flopping, defenseless fish is like saying "Come eat me!" to a bullfrog.
(The rest of the frogs I will release into the pond where I got the treefrogs at, since I already see them there.)
Sounds good. Just be sure to use dark lettuces like romaine; iceberg lettuce is nutritionally empty. Other greens like spinach and kale are also good.
When your Pseudacris metamorphose they will be far too small to take even pinhead crickets; plan on getting some fruit flies. The bullfrog will be big enough to take medium crickets when he metamorphoses. I would caution against goldfish as the steady food for your bullfrog; no doubt he'll eat them, but earthworms, waxworms, fortified crickets, moths, and pinkies provide superior nutrition.