Hi guys, i checked my betta's tank earlier today and it didnt feel warm like usually but i didnt worry about it. Just a minute ago i went to see if it was warm and it was still pretty cold. And the heater itself was not warm to the touch like it usually is. I have unplugged it and plugged it back in and i am now waiting for it to heat back up (takes up to an hour). It is a Hydor mini heater for 2-5 gallons 7.5 watts that i got from petco. I have it in my 4 gallon. Any suggestions on anything i can do to make it work? Also, have you used one? Any problems with yours?