Yes I am running 2 heaters in that chambe Just have to make sure heater is off when I do a water change.Do you have the heaters in the same chamber as your return? I keep hearing that is a bad idea, but I’m beginning to wonder if that is the only area this tank was designed to have them. Right now my heater is in the one of my sock chambers but I’m thinking about using that chamber for more floss
To make it failsafe I put the heater control and return pump on the same switch, so when return is shut off, heaters are automatically turned off as well