Having the ability to monitor the salinity of your reef tank is a very valuable piece of information. Usually, if something is to go wrong with your tank, you will usually see a change in salinity from temp, to a top off unit being stuck on, if you have a Neptune Apex Controller we highly recommend investing in the PM2 module and salinity probe.
Add the Salinity Module: PM2 to your Apex Neptune System.
Real-time monitoring of salinity in reef aquarium
Module has extra Temp Probe port
I/O Switch Inputs for ATO, feed buttons, leak alarms, etc.
Probe Sold Separately.
Neptune Systems Salinity Expansion Module:
Monitor/Control Conductivity/Salinity and temperature