You've got your Apex mounted, connected to your network, and you've updated your Apex AOS (DO NOT proceed any further in the setup process if you have not yet updated your AOS), so now you're ready to get your probes connected and calibrated.

In this article, we will guide you in connecting and calibrating your salinity (conductivity) probe.

It's worth noting that this probe is designed to measure salinity in your aquarium based on a conductivity reading. To read more about measuring salinity through conductivity, check out this article by Randy Holmes-Farley.

Connecting Your Salinity Probe to Your Apex

Begin by identifying your salinity probe and the port it will connect to.

Also, please remember that all of your probes are fragile and should be handled with care.

Your salinity probe is the longer black probe that came included with your Apex.

NOTE: Your salinity probe should be dry to begin the calibration process do not rinse it or do anything to get it wet.

Your salinity probe will connect to the port in the lower left corner of your Apex base unit.

Now, connect your salinity probe to your Apex base unit as shown in the video below.

Now that your salinity probe is connected to your Apex, you can proceed with calibrating it.

Calibrating Your pH Probe

To begin calibration, you will need to log in to your Apex. You can do this operation from either your Apex Local Dashboard or Apex Fusion (our article for connecting your Apex to Fusion can be found here).

This article will demonstrate this operation as performed from Apex Fusion.

First, log in to your Apex Fusion account.

Then, from your Apex dashboard, click the configuration button.

This expands your Apex controls.

Next, click the inputs button.

This will take you to your inputs configuration page. On this page, select "Salt" as shown in the image below. This will take you to the salinity probe configuration page.

Once on the salinity configuration page, click the Automatic Probe Calibration button.

You are now beginning the calibration process. Click "Calibrate" to continue.

Your calibration will begin by verifying your dry probe's readings. Your probe should still be dry at this point of the process. 

You should see indicators showing that the probe is 1) reading in the acceptable range, 2) settling in on a reading, and 3) counting down toward completion. (While you will see a timer, your probe may may complete calibration before the countdown is finished.)

When your dry calibration is completed, you should see all 3 check marks as in the image below.

Click "Next" in Fusion to continue.

The next screen should indicate that you will calibrate the probe with high conductivity calibration solution.

For this step, you will need the salinity calibration solution that came with your Apex.

Place your salinity probe in the calibration solution, and click "Next" in Fusion.

You will once again see that Fusion is calibrating your probe with the indicators of acceptable range, settling of the reading, and time remaining for calibration.

If you notice that your probe seems to be having difficulty reading in the acceptable range (as indicated by a red caution triangle), gently shake the probe in the solution.

When the process has completed, you will again see all 3 check marks indicating your salinity probe has completed its calibration.

Click "Next" to see the verification that you have completed the calibration process.

Now, place your salinity probe in your sump. Your probe should ideally be placed in a probe holder of some sort designed to hold it in place.

Make sure that your probe end is completely submerged in the water, but ensure that the wire end is above the water's surface. When using a probe holder, be careful not to over tighten the screw holding your probe in place as you may damage the probe.

You will now see readings of your salinity probe in Apex fusion.

If you would like to adjust the preset minimum and maximum value range of your salinity probe (these control when you will receive alerts from your Apex about your salinity levels), click on the gear icon located above your salinity readings. This will take you to the conductivity probe configuration page.

Congratulations! You've successfully connected and calibrated your salinity (conductivity) probe!