I've tried everything with the Apex and salinity... Used a VCA kit, tried upside down, right side up, inside out all the tips and tricks. None of it did it for me.
Frankly it works in my case on both tanks by being in a fairly low flow section of the sumps and try to keep electrical interference away from it. Everything is liable to cause interference if it's plugged into an EB8(4)/EB832 (seems to be more sensitive). At one point I could tell when my T5 lighting would come on and go off as the numbers shifted 2ppt, daily, accordingly.
I'm on a few different online emails chains for the availability for the Hydros Launch controller, as I will go fulltime with that module and retire the A1 Apex I'm using currently with the probe in my earlier post.
As you saw, the Pasco probe we have deduced is the same one Neptune uses, just with a proprietary connector (which sucks) as Hydros just uses the standard bnc for its probes. The fact that they are more open to using another brands product in their ecosystem makes me want to take the plunge, badly.
Which bnc to mini din adapter did you use, all of those that I've tried that are in the wild aren't "pinned" properly for the apex?!