I am in the process of building my own aquarium. Final result, if all works out and the box stays together
, will be a 230 +- tank. Does anyone have any experience with those under-substrate heaters??? Can I use more than one unit at one time??? that one sounds like a no-brainer. Best question is probably, does anyone have a suggestion on heating that much water economically???
P.S. This will be a FW tank.

P.S. This will be a FW tank.