Tunze Osmolator 3 help needed

[Chessmanmark]

Last week my Tunze Nano ATO stopped working after a decade of faithful service.

I bought the new ATO 3 and installed it today. I run it in my 40B w/o a sump. When I plug it in it pumps water but when the pump stops red lights blink on the sensor. As it is new there isn’t any salt creep on the sensor and I can’t find any resolution to my problem on Google.

I’m looking for advice on my next steps.

 

[Chessmanmark]

After trying different things I submerged the sensor deeper into the water and the light turned green.

 

[rvitko Verified Sponsor]

Blinking red means it timed out, just like the old unit had two time limits, so does the new one, but they are considerably shorter as the pump is stronger, 77 and 154 seconds, as explained in the manual which is on the website, you plug and unplug the power 3 times at the barrel connector to set the time limit, a rapid white flash means you are in extended time.