Bests & Worsts Reviews from Amazon

Purchased for a 20 gallon hermit crab habitat. Rather than using the heater under the tank, I placed it on the exterior back glass, all the way to the left above the substrate. If you are using this for a hermit crab, they prefer a warm and a cool side of their substrate, so it's best to stick the heater just above the substrate line all the way to one side or the other. Using the heater under the tank can actually be bad and cause issues with molting because it will hear the substrate but not the air, and the substrate will be too hot. I hour my review helps! I've gathered this info from several sources, and I think it's nice to have it all in one place.