mounted 2 per 3 gal square used mayo buckets, one per side and I can set the buckets up on a cinder block that way to keep them off the ground. Drilled a tiny tiny hole in the lid so as to prevent a vacuum and keep the nasties out. I do use a small 80W heater in one in weather below 30 deg. Usually a few minutes of wrapping your hand around one if it freezes will thaw them out. Have yet to have one freeze and break, they're cheap so it is easy to keep a couple on hand as spares or for parts.
