My den where the tank is has a winter temperature of 68 +/- degrees. The Alk containers are against the outside wall of the house... only spot it can be. No room next to sump to use tank water. The Alk solution crystallizes at low temperatures. Need an idea of a way to heat the containers to about a steady 75 degrees. I been thinking about wrapping water pipe heat tape around the Neptune plastic containers (have 4 total with Mg & Calcium per Triton). Don't know if this will be safe. Used Betta heaters in the past but these heaters heated the solution to 80 degrees or more as the Alk got used and lowered. Placed my wall warts close to the containers but it is not enough when it really gets cold outside in New Jersey. Wonder if any DIY's can supply me with some ideas.