Weird temp sensor problem

[Slartibartfast]

When my T5 comes on, my temperature sensor drops about 2 degrees for about 5-10 minutes. This is an a 156 G, so I assume the temperature is not really dropping and this is an anomaly.

This is kind of annoying because it sets off my low temp email alarm every morning when it happens. You can see it in the attached graph.

My temp sensor is in the main tank. I had to remove it from the sump because it was too close to the heaters.

Any ideas what causes this? Or a workaround?

 

[Deleted member 143833]

Apex or AC3? What firmware version?

It could be some electrical interference; you might want to call Neptune and have them walk you through a few tests...

 

[aquamanic]

You could temporarily remove the temp probe from where it's at, drape it in the front of the tank and have the probe cable way away from any other electrical device. Then give it a day and see what happens. If the problem goes away then Ken's right and you have interference of some sort.