Bull frogs are easy, sort of. Give them plenty of CLEAN, chlorine free water. Keep the water quality good with a cheap filter, and an in tank one should wok best. DO NOT put in tank decorations from outside!! ! They often contain many poisons and heavy metals that will kill the frog. The tank size should be small, no more than 40 gallons, but no less than 20. I had a few Bullfrog deaths due to a large cage giving them enough space to jump and get to deadly speeds. Food-wise, you'll need at least 100 crickets a week, and that is underfeeding them! Oh, and the filter should be a combination filter that has a built-in heater. Set the temperature of the water to 72 degrees, and leave it there. Too hot, and it'll speed up the frog's metabolism, too cold, he could die.
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Spring is the season when the hawks all start to fly, Well maybe when I die we'll trade places, I'll grow wings and I'll fly, Hey, Blue John, hey Blue John, Heyyy Bluuuue John, Can I Play with you?