Water temperature is at 82!!

[Dgameman1]

I went out and upgraded my heater to an Eheim heater and set the temperature to 78. When I came back home 4 hours later, the temperature was 82 and I think it's because of my t5ho bulbs. So, I set the temperature on the heater to 75 and it's still at 82 and then before I went to sleep, I turned off the lights and set the heater to 78 and when I woke up it was still 82..

What gives?

 

[Dgameman1]

. I didn't know I had to calibrate the heater. My baaad

 

[melosu58]

The proper temp for a reef is 78-82. You were fine with it at 82.

 

[eric faatz]

I never heard of having to calibrate a heater before,that's a new one for me.I thought you just set the temp and it would be fine.

 

[Brookster123]

I find with my heaters that are rated for larger tanks I have to keep the dial setting lower, at 75 to keep it at 79*