Can anyone suggest what to do about my tank temp rising. My 55 gal tank has risen to 84 F today. I have had the heater unplugged for a couple of weeks now. Can it be the 9w UV sterilizer with a rio 400, or maybe the Super skimmer w/ the 1100 rio? I am at a loss here and I fear I may lose my fish. The temp doesn't fluctuate at all it has just risen recently. The outside temp has raised in the past few days, but not too high. I dont' understand what can be heating my tank so much (its not in direct sunlight either). Please help!