I have been living off-grid for five years and am now hooked in. My filtration system is an upflow similar to what I think Ron's is. Due to previous power restraints I have a loop off my boiler heating my two 55g insulated barrels. Now I want to add heat tape to the mix. I've read lots of posts but have not been able to find what type people are using and how they are regulating their temps. Also I have pastic barrels and was unsure if they could take the direct heat from electric heaters. Am I going to have to change my main settling barrel to a metal one? I have been using this system for a while now with no problems but propane is expensive and I think I could heat for less with electricity. I need advice from the pros!

There's a detailed description of Ron's heated system halfway down the page at this link
http://www.burnveg.com/forum/viewtopic.php?t=9

Thanks John