I have my 28 gallon nano HQI tank up and running now. Looks great so far. But one problem has come up that I do not know how to solve. When the lights are on, the water temperature rises to 80 and 81 degrees. I only leave the lights on for about 8 hours, and the fan is working. What can I do to keep the water temp down? There seems to be plenty of flow. :sad: