Apex Classic Setup and Programming Guide v2.2
Page
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The Apex system uses a 2 point calibration system which results in very accurate
readings between the 2 points and less accurate readings outside the points.
Choose the calibration solutions based on the range of pH the probe is expected
to read. See the table below for recommended calibration solutions:
Expected
Range
Low
Solution
High
Solution
Fresh Water
Aquarium
6.0 - 7.5
4.0
7.0
Salt Water
Aquarium
7.8 – 8.5
7.0
10.0
Calcium
Reactor
6.5 – 7.0
4.0
7.0
Table 1 - Calibration Solutions
NOTE: For best results, use pH calibration solutions in packets as the solution in
bottles tend to shift pH after they have been opened.
To calibrate a pH probe:
1.
Acquire the proper pH calibration solution packets and place in aquarium
water (unopened) to acclimate them to the system temperature.
2.
From the Apex Display, open the pH calibration menu: Setup – pH Setup –
pH Calibrate.
3.
If you have more than one pH probe enabled on your system, use the
up/down arrow keys to choose the probe you wish to calibrate, press Select
or OK.
4.
Use the up/down arrow keys to select the value of the Low Calibration
Solution used, push Select.
5.
Dry the Low Calibration Solution packet off and carefully open the corner of
the low solution, just enough to get the pH probe inserted in the packet.
6.
Remove the pH probe to be calibrated from the tank, rinse it in probe
storage solution (or tap water), gently shake the excess solution off the
probe, and place the probe in the Low Calibration Solution. Periodically
swirl the probe in the solution to ensure an accurate reading. Ensure the
probe is submerged in calibration solution at all times.
7.
Wait for the low reading to stop changing. This may take a few minutes up
to 5 minutes depending on the type and condition of pH probe being
calibrated. The value of the reading while calibrating may not match the
value of the solution being used, this is normal. Once the reading has
stabilized, press Select or OK.
