Today on BRStv we have our ninth episode of the Neptune Apex series and we are going to
show you how to calibrate your salinity probe.
Hi, I'm Ryan host of BRStv where each week we cover a new topic related to reefing.
This week we are going to calibrate our conductivity probe, often referred to as the salinity probe.
There are some pretty important differences between this probe and others.
The first is it is super fragile so don't go whacking it on anything during the calibration
procedure or you will regret it.
Second is it has some tiny holes drilled on the side of the probe.
These are to let the air out that can get captured within the probe.
It is really important that you place the probe in a location that is unlikely to produce
lots of bubbles like right next to the skimmer output.
These tiny bubbles can collect inside the probe tip and result in inaccurate readings.
Finding the right place for the probe is critical because even the tiniest of bubbles will collect
here and mess with the reading.
The cord is also more susceptible to interference issues than most probes so try and keep it
away from power cords, especially ballast cords.
If you are having issues disconnect the cord and try to route the cables in a way that
reduces the noise from other equipment.
The first thing you need to decide is if you want to connect a second temp probe to the
PM2.
Connecting a temp probe directly to the PM2 will result in more accurate measurements
but it isn't absolutely critical.
The only real difference from a calibration perspective is if you don't use the second
temp probe you will leave the temperature compensation at zero.
I personally feel that if it is worth measuring salinity in the first place it is worth trying
to get it as accurate as possible, especially because I dose two part to this tank which
will raise the salinity over time.
Because I am using the temperature probe we want to change the temperature compensation
to two point two.
It is also possible to just disconnect the temp probe from the apex and move it to the
PM2.
If you do this you will have to make sure all of your temp controlled outlets are running
off the correct probe as well as swap all the tiles out on the display module and fusion
dashboard.
The next thing we want to set is the range.
Low is typically used to test purity of fresh RO/DI water, medium for freshwater tanks,
high reads in conductivity for a saltwater tank, and salinity reads in parts per thousand
which most people are more familiar with and what I suggest.
The first step in calibrating your salinity probe is to take it out of the tank, dry it
off, blow the water out of the end and let it dry.
I suggest letting sit there for a couple hours to get completely dry.
It is critical that there is no moisture present between the contacts within the probe.
If you haven't put it in the tank yet and it's dry you can obviously skip the drying
step.
Once it is dry hit the conductivity calibrate button it should say dry conductivity probe
and settling with a number.
Once the number stops moving for ten to twenty seconds go ahead and hit ok.
During this time you should float the calibration solution in the tank or sump so the solution
is the same temp as the tank.
Now select the solution you are calibrating with.
A vast majority of saltwater aquarium owners will use a 53,000 solution which is thirty
five parts per thousand or approximately 1.026 specific gravity, Select that.
Now clip the corner off the solution and insert your probe and hold the calibration with the
probe in the tank so it maintains the same temp as your temperature probe which is critical.
Try and make sure one of the air holes on the probe is turned upwards.
Give it a few light taps with your finger to get the air out and wait for the settling
number to stop changing.
Remember this probe is fragile so don't whack it against the sump to get the air out.
Don't be concerned with what it says, only that it stops moving for ten two twenty seconds,
try tapping it again to see if there is any more air in the probe, if it doesn't change
then hit ok and the probe should be calibrated.
Confirm this by leaving it in the solution and checking your home page to see if it reads
very close to thirty five parts per thousand.
Remember if you do have any issues with this process the first step is to remove the probe
completely and isolate the cord from electrical noise, throw the temp and salinity probe in
the same cup to completely remove the stray voltage issue and see if the if the readings
look reasonable now.
If you have any questions about this process or tips for your fellow reefers check out
the comments area down below.
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week.
See ya next week with another episode of BRStv.