I have a 50gallon tropical community tank. In the tank i have... 8x Boesemani Rainbow 6x Congo Tetra 10x Kuhli Loach I usually aim to keep the temperature around 78. But recently the tank has been going up to 80. Ive also noticed Brown algae creeping around my tank and its covering a great deal of my heater. Would algae cause the heater to overheat the tank? Whats the best way to clean it? Or is it best to replace it? Any suggestions on a heater?