If these are your White's Tree frog; that might be a challenge and recommend you move them to a warmer location. White's need 85F during day (with slight drop at night) in a well ventilated enclosure. Providing that with a space heater on a large basement is going to be super tricky. A heat source like a dome with a ceramic heat emitter and maybe in combo with a large heat pad can be used to help raise temp from a normal temperature room. If your basement temps drop a lot (what is temp there on worst Winter nights?) because it's and unheated place; it might just be better to move the enclosure from there. Good luck

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