:You don't need to...as long as you keep the temp. at around 80 degree and can drop down to the high 60 at night . Frog don't like it toasty like reptiles; they like it cooler because they are prone to descication ( spelling ). Frogs looses water really quickly. I would found mine sitting in the water dish in the morning at around 65-70 degree after a night with the AC on.