Frog poo is a sign.. Also, watch the weight.. as long as it stays thick in the waist area.. your fine.
Another good sign is being alert and active in the evening. Keep the tank moist and humid. Don't worry about feeding in a seperate tank (most of the time, that just stresses the frog and does more harm than good, it should only be attempted in extreme cases).
Another good thing to do, feed in the same place at the same time each night. Not knowing where the frog came from or the age of the frog, I would advice you the safe way.. feed it 3-4 crickets a night for now, crickets should be about the size of the distance between the frogs eyes. Dust the crickets with vitamins and calcium (very important) one or two times a week. I would do this for a month or two since it is a new frog. Then based on the size, I would guess the age and adjust accordingly. I feed 0-2 months 3 times a day, 2-8 months every day and then 8 months on get feed every 2-3 days.
Alot of times the worst thing you can do for a retf, is try to help to much. Watch it from a distance of atleast a couple of feet.. and try to stay out of the tank as much as possible, atleast for the first few months.
Also, there is a good caresheet on www.amphibiancare.com, do yourself a favor and check it out. It is not the definative word on RETF's, but it is one of the best caresheets that I have found.
Good luck w/ it!
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