Issues with Neptune FMM ATK Alarm

[gallid19086]

Hi everyone,

I have a Neptune FMM set up on my main 125 display tank in the sump with an external fresh water reservoir being used as an ATO system. This is stand alone. 1 have one other FMM ATK stand alone on a different tank, but they are NOT connected and I do not have a master control unit as I don't own any other Neptune devices.

It was working fine for months, but is now constantly throwing the 2 beep alarm, which according to the website, means the high level sensor in the sump. I have repeatedly cleaned, dried and adjusted the magnetic mount with the float and sensor. I've checked the wiring. Any advise on what I can do? As stated, I don't have any way to get more information (other than direct USB connection to a laptop) and I am NOT willing to buy the master control unit. Could this just be a malfunctioning optical sensor? Are they replaceable in the sump unit (looks glued in)?

Full set up for reference:
Sump: cut off float and the 2 optical sensor magnetic assembly
Reservoir: Pump and optional optical sensor plugged into port 4 (low water level alarm)
Current sump water level is just at the lower sensor so the ATO should be silent. There is no water turbulence or splashing in that part of the sump.


It should be noted that I have another one of these FMMs on my smaller BioCube tank and it works just fine.

 

[Formulator]

Sounds like its time for a new optical sensor. They are notoriously error prone. I gave up on getting consistency from them in any application where they are primarily kept dry and only wet from time to time (like high water alarm). When they are kept primarily submerged they seem to do fine for some reason. I switched to the Avast ATO system for exactly this reason. Almost every other ATO system on the market uses the unreliable optical sensors, but Avast uses a unique pressure switch that is bulletproof IME.

 

[gallid19086]

Sounds like its time for a new optical sensor. They are notoriously error prone. I gave up on getting consistency from them in any application where they are primarily kept dry and only wet from time to time (like high water alarm). When they are kept primarily submerged they seem to do fine for some reason. I switched to the Avast ATO system for exactly this reason. Almost every other ATO system on the market uses the unreliable optical sensors, but Avast uses a unique pressure switch that is bulletproof IME.

Thanks! Yes, it's those v2 sensors. I ordered a new v2 sensor and one of the newer magnetic versions. Once I unplugged the "2" cable, it stopped alarming. When either of these boxes fail, I'll certainly consider the Avast ATO.