Ok.. I have the heater from WalMart.. 100 W in a 29 G tank. 2 days ago I did 25% PWC
and forgot to turn the heater off. It was only exposed about 2 inches below the "water line" marking. I kept an eye on the temp and it stayed steady 78 degrees (using one of those sticky therm.) . Today I put in a new CoraLife digital thermometer, and when I read it, it said 80.4 degrees! I still had the sticky on, so I look, and sure enough, it read 80 as well. So I turned it down a bit, checked an hour later and it read 80.8 degrees! Now.. how much should I turn this thing down?? It has degree markings on it.. so a degree at the time? How often?? Could it be overheating? ARGH! I know that changing temp too quickly can stress the fish.. HELP!!!
Oh yeah!! Where in the aquarium should I put the probe for the thermometer? Right now I have it on the total opposite side from the heater, about halfway down the side.. Thanks!