I have no idea why but for some reason I'm having the following problems. First, my 30 tall is set on 77 F but it measures 82. Second, my 75 gal is set on 74 F but measures 84. This is weird because my house hasn't gone above 78 degrees this year and the lighting doesn't produce much heat on either. This is bad news since I'm soon getting a native (probably a pumpkinseed) in my 75 and I'd like to get it down to at least 78 before I do, also the Corydoras in my 30 really don't like the hit water. I plan on doing 50% on all my tanks tomorrow and for these two I'm going to add really cold water (not to cold it'll shock them but around 65 F) to try to lower temps. If anybody knows any reason for this or other ways I can lower and keep it down please let me know.