Look for small porcelain heaters. They should make some small enough to fit in your box. I have herd of folks using them in cabs with good success. Also, a heating pad may take a little bit of the edge off.
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BlueBear Reviewed by BlueBear on . How best to heat a small grow cab? I'm after some help on how to heat a small grow area of 2'w x 1.5'd x4'h thats in my attic. Temps are around 20 C in the day, not sure what they are in the night, probably drop to around 14 C so i want to do something before it gets any colder. I've looked at the cheap electric fan heaters, but they all seem to powerful for my small cab, they say not to use in a small area. I know you can get oil filled greenhouse heaters, but i don't like the idea of using oil indoors incase it gets knocked Rating: 5