Apex Conductivity

i dont have one, but most posts say that you should only use this to indicate changes in salinity, not to actually measure it. still is likely to be all you would really care to use it for along with the apex as long as you know your starting point, IMO. may want to search a little on Reef Central's Neptune forum as there are quite a few varying opinions.
 
I dont think I would ever use it to measure it, more of something to give me an idea where my tank is when I am away.
 
I used it with my previous Neptune pro unit and found it too inaccurate to trust unless I recal'd it really often. It would vary by 3 or 4 units throughout the day so I chose not to pay for the module on my Apex. My topoff is gravity fed so I simply control the number and duration of topoff, I do it three times a day in 10 minute increments. You can also monitor topoff times/duration in the Apex log's.

Cheers,
 
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