Reef Angel Forum

If I unplug my lower ATO float my PH probe reads correctly, also with the float unplugged and the higher float submersed everything is ok indicating an issue with only the one lower float.

Is this typical of floats getting older, they are less than 2 years old?

Very typical. They are pretty cheaply made. You can get a 5 pack for under $10 on ebay. Probably less...