Originally Posted by potatochobit
you live in NY and you don't use a heater during the winter?
I would say it depends on what kind of lighting you are running and how close it is to the water line. For instance, my tank maintained a constant 79 while I ran 2 T5HO lamps at about 6" above the water line. Just changed to 6 T5HO mounted about 8" over the water line and now it stays at about 81-82. I am watching very close to see if I am going to have to run a chiller or not. If you are running Metal Halide lights, the heat from them may be even greater.