[rblong]

Excaliber - I suspected the fan slowing down also, but using a digital submerged in the same water and the water temp is not actually changing - just what the gauge is reading is changing. I will use a strobe on the fan just to make sure though.

Yea, these kind of things, even though not serious, bug the heck out of me till I figure them out. I'll bet that radio thing was a hoot to figure out!