My Betta is in a 20 gallon tank and I use a Marineland Visi-Therm Submersible Aquarium Heater 100 watts which said it should be good for 29 gallons. The thermometer on the heater shows the tank is at 80 degrees yet my betta refuses to move away from it. He is constantly floating in the same place by the heater unless I'm feeding him. I don't think he's sick so I didn't put this in the "ill fish" part of the forum.. could just be a character quirk but I was wondering if anyone else experienced this with their bettas? I checked the water parameters today as well PH of 7.5, no detectable levels of nitrites, nitrates or ammonia. I do about 30% water changes every day to every other day depending on how busy I am. Btw is that too much? I'm new to the hobby so maybe I'm over doing it?