i got mine a week ago and put it in my 135 first thing i learned was that i need more than 300 watts for the tank so that aside... here's the other problem i'm having no matter where i set it, it is ALWAYS 1.5 degrees below the set point. is there something wrong with this heater? is anyone eles having these kind of problems? let me know what you think of the "E" line of heaters from Fluval.