I actually just started using the lighting system a few days ago after I received my chiller. It is a quad reef lighting system set up for a nano tank. Between the lights and the wavemaker pumps built into the system, I could not keep the tank under 80 degrees. I just got the chiller this last Tuesday and started using the lights that day. With my new chiller electonic temp controler, my temperature keeps between 76 - 78 regardless, unless I change the settings.