Neptune apex salinity probe calibration

[mmorrison55]

On a Neptune apex system, What salinity reading would (should) you get when using the Conductivity 53000 uS/cm solution after calibrating the salinity probe?

Im suspecting my probe may be going bad. It was reading close to expected, then I tried to lower my salinity a bit by replacing a few gallons of tank water with RODI. I may have removed a bit more than intended as the measurement went way down (from 35.7 to 26 ppt). When cross checked against my Milwaukee digital refractometer, which read 32 and 33 (it would fluctuate between to two so it must have been right on the edge of 33.)

before I lowered my salinity, the Milwaukee was reading 35 while the apex 35.7 and had been creeping up over the last week. I was trying to lower it a bit so that it didn’t get too high.

Anyways, since adjusting, the discrepancy is way off between the two now. I added a small amount of hyper salinity water to get back to 35ppt on my Milwaukee, but my apex was still showing 29. Figured I was due for a calibration, so I broke out a pouch of the calibration solution and when doing the automatic calibration it would not complete. Second attempt at manual calibration succeeded but it showed 39ppt while sitting in the 53000 solution. After putting the probe back in the sump holder, it’s reading 32.6 while my Milwaukee is still reading 35.

So better than the 6ppt difference before calibration, but still not instilling the confidence i was hoping for of having them close.

 

[Tangdora]

Should be right at 35ppt after calibration +- maybe a tenth of a point. The probe can get very finicky during calibration though. need to get all the air out of them a make sure the temp of the solution is at tank temp. Also I personally only calibrate using apex local as I think i gets bad calibrations when using the fusion app.

 

[mmorrison55]

Should be right at 35ppt after calibration +- maybe a tenth of a point. The probe can get very finicky during calibration though. need to get all the air out of them a make sure the temp of the solution is at tank temp. Also I personally only calibrate using apex local as I think i gets bad calibrations when using the fusion app.

Ahh thanks… I forgot about floating the solution. That could be my issue. Will try another batch

 

[NC2WA]

Should be right at 35ppt after calibration +- maybe a tenth of a point. The probe can get very finicky during calibration though. need to get all the air out of them a make sure the temp of the solution is at tank temp. Also I personally only calibrate using apex local as I think i gets bad calibrations when using the fusion app.

Apex local? What do you mean? I was going to use fusion but connecting via desktop, not phone.

 

[mmorrison55]

Apex local? What do you mean? I was going to use fusion but connecting via desktop, not phone.

1. You open a browser
2. in the address bar type apex.local
3. in the logon prompt type admin for the user name and 1234 for the password.

That works if you have not changed the default name of the Apex or the local username and password. If you have changed the name use that name instead of "apex" in the address.

 

[Tangdora]

Apex local? What do you mean? I was going to use fusion but connecting via desktop, not phone.

the post above describes how to access. But from a logical standpoint apex local is a LAN (local area network) basically meaning that when you connect to apex, probe signals are going straight from apex though your router straight to your device. Signal only has to hop one time resulting in very low latency. When you communicate though fusion your apex is basically using a WAN connection (wide area network) this means signal is going through your router out, out your house to their sever then back to your router then to your device. This increases latency as the signal hop around the country. For normal operation it mays only take a second or two for signal to leave and come back. But when your calibrating that second or two can make a big difference whether or not the needed is sitting on 100% or has retracted back

 

[Ziggy17]

It drifts quick. I stopped using the probe. Got tired of calibrating every week. I just use my TM Hydrometer once a week and seems to be fine. My ATO keeps me where I need to be.

 

[Tangdora]

It drifts quick. I stopped using the probe. Got tired of calibrating every week. I just use my TM Hydrometer once a week and seems to be fine. My ATO keeps me where I need to be.

Not to play devils advocate here but can’t say I ever had drift on mine. And always have a reading close to my own TM when doing weekly t
Comparisons. if your getting drift key to avoidance imo is making sure it’s in area of the sump with high flow and no micro bubbles, making sure the tc factor is set properly. And make sure your reading as close to 35ppt solution post calibration.

 

[mmorrison55]

ive since cleaned my probe and recalibrated, and all three of my current salinity checks are with a few hundredths of one another…

So im good.