Tank Temperature Concern

[droidus]

Not sure if this helps, but thought I'd provide a picture of what I am working with:

 

[Crustaceon]

My tank ran at 79 last night and is sitting at 82 right now. This is with acros and other sps. Last year it stayed at 84 for a few weeks on end. If your tank doesn’t look stressed, don’t worry.

 

[lapin]

So with the lid cracked open, and the top feeding hole open, I am still getting a reading of 82.1 degrees. I have my heater set to 79, and noticed that the light was on...

The tank wont be 79F if the heater keeps coming on at 82F