Temp...problems advice needed

Just went through the same with mine. Have 2 Jager 250w heaters and my tank was consistently reading 82 Degrees. One of the heaters was way off and was causing the overheating. Disabled it and within about 4 hours temp was where it needed to be. Both of these heaters are new out of the box. I will be returning the faulty one tomorrow,
 
If you have glass tops on your tank you can remove them and that will help. Take 3-4 pop bottles if you have them and freeze them and put 1 or 2 in your sump and that can help, I keep 5-6 froozen all the time just in case. PC's are known for getting hot and warming up tanks, if you have a clip on fan use it on the display or sump/fuge and that will help a lot.
 
You want to try and get yourself an ATC300. You plug your heater directly into in to and set the temp range you want it to turn on at. You pop the probe in the water and the digital temp display lets you know whats going on. It takes full control of your heater. My temp never goes above 26 and never below 25.3 thanks to the ATC
 
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