White substance around temperature probe

[RedsQeezy]

The temperature probe from my heating controller has a strange white substance around it. The tank is still holding a steady temperature but the heater constantly switching on and off. I have taken it out of the tank for now and am using a back up. Dose anyone know what could this be or caused this

 

[TriggerFinger]

It looks like salt creep?

 

[RedsQeezy]

It looks like salt creep?

Its more of a yogert like consistency

 

[Flippers4pups]

What comes to mind is it's leaking at that joint. Clean it well and see if it improves. If not, look into a replacement. Best of luck!