Trouble with Hydor 25 Watt heater.
I bought this heater a little more than a month ago to heat up my 2.5 gallon, but now it's been moved to my 6.6 bookshelf tank that houses my Betta and four Ghost Shrimp.
It's set at 79 degrees, but I found out when I got home this evening that the water temperature was 84 degrees and the light was still on.
So, I lower the temp to shut it off. I then turn it back up to 79 and right now the light is back on and my tank's temp is at 82.2
The thermometer and heater are at opposite ends of the tank.
Has anyone used this heater and have trouble with it? I don't want to leave it on all night, but I'm afraid with the weather getting colder at night, I'll wake up to a dead fish in the AM.