I use two heaters in a 200 gallon. Both are on 24 hours a day. Temp is constantly 78-80f. The trick is to get it like that at the right wattage so you dont need to rely on a thermometer because you know the heater cant get any higher. Temp is cold here most of the year and so is my basement so im good.Yeah, I normally maintain 78F but I stopped manually checking. The probe on my 2-1/2 year old heater seems to be failing as it was reading 6 deg off. I played with a refugium and frag tank and I ran out of outlets so I removed my redundant heater. Sigh.


