fluctuating

I live in Pa. In the summer we run the air conditioner on hot days but not on warm days (around 82 degrees) So our house temp fluctuates. I keep my betta tank at 78-79. But on hot days the water temp goes to 80 or so then lower at night. I leave my heater in the tank set to 77-78. The other day...

Hi everyone! I'm a new betta owner and I really want to do my best to take care of my little guy here. I have a 3 gallon tank with a filter and a preset marina 10w heater. The filter and heater have been running for 2 days now but what concerns me is that in the morning, the tank temperature is...