Yes, a 75 would be a bit intimidating for the little guys, but so would a 30 gallon :P.

You could easily keep the froglets in a 10 gallon until they get bigger. When I first purchase frogs I put them in a 10 gallon with wet sphagnum, a brom or two, and some pothos and creeping fig cuttings. It gives you a chance to monitor the frogs health before you put them in their permanent vivarium. I do this with all the frogs I purchase, including seemingly healthy cb frogs. Its a good habit to get into, and really makes things a lot easier (and cheaper) later down the road.
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A room of herps.
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