I have a hydrofarm T-stat hooked up to a 20 dollar fan powered heater from Lowe's. It raised my electric bill about 15 bucks a month and I keep it at 74 which leaves the room 72-75 and gives some wiggle room in case the heater for the house kicks on and heats it all at once. I have crested geckos in there and they'll die over 80 degrees for a period of time, so I play it safe.