I have never used heat tape before, always UTH's, but as the temperatures here in the Midwest are getting cold, I've decided to try heat tape because it seems better since I'm going to have to do it on the hot side and cool side (I have a Ranco thermo. and Herpstat thermo. to regulate the different sides). I was just curious if someone could give me a little insight on how it works. I see they sell the 11' at 20 watts per foot. So, how much would I need for a 20 gallon for each side? Also, I'm thinking of using the Eco Earth Coconut Fiber as substrate to help with humidity ( I'm going to have to start using space heaters for myself, so I want to make sure there is enough humidity in the viv). Is it okay to use flexwatt heat tape with this substrate? I have tried to read about the heat tape, but some of the information is still unclear. Any advice would be great!