Neptune Systems pH Calibration Fluid (discontinued)

pH Calibration Solution 4.00
Use this solution to calibrate your pH probe primarily when you will be using it in a low-pH application such as a calcium reactor. It is not usually used to calibrate your pH probe for use in your aquarium itself.

pH Calibration Solution 7.00
Use this solution to calibrate your pH probe.

pH Calibration Solution 10.00
Use this solution to calibrate your pH probe. This is the most common solution to be used to calibrate your pH probe for monitoring pH in your aquarium when paired up with the 7.00 pH Calibration Solution.