So I convinced my roommate to get a heater for her male betta he is really big and she has had him for about a year with no problems. His temperature is always around 70 but Im sure it fluctuates at night. She is going to try a heater but I want to know the best way of acclimating him to newer warmer water. What is the best temperature for him? He acts really depressed and super lethargic when the water is too hot after water changes. He just lays in the gravel and does not respond at all until the temperature drops. Last time the water was at about 80 and we floated him for about an hour and released him but he still acted really funny not swimming at all just layed on the gravel.