Yea, as soon as I read what you had to say, I went over to check on it and the light clicked off. It's reading 80.4, so maybe the temp was uneven in the tank.
I just did the test for today:
ammonia = 0.25 ppm
nitrite = 5.00 pm
nitrate = 10 ppm
Nitrite seems to be steady and Nitrates doubled over night.