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A meter that drifts even slightly out of calibration can send an entire feeding schedule off course. Aqua Master Tools' pH 4.01 Calibration Solution resets your equipment, including the Aqua Master Tools P110 Pro Combo Pen, to a precise, NIST-traceable reference point, so every reading that follows can be trusted.
Sold as a case of 18 bottles at 100ml each, this larger format is built for shops, commercial growers, or anyone calibrating meters often. To keep your sensors in peak condition between uses, we also recommend stocking the Aqua Master Tools Storage Solution KCl rather than relying on single-use sachets.
Certified pH 4.01 formulation calibrates meters to a recognized national standard.
Ships as a case of 18 bottles, ideal for frequent calibration or commercial use.
A larger volume per bottle than single-use sachets, suited to repeated calibrations.
Stays accurate when stored between 15-25°C, ideal for grow rooms, tents, and labs.
| Specification | Value |
|---|---|
| Solution Type | pH 4.01 Calibration Solution |
| Volume per Bottle | 100 ml |
| Bottles per Case | 18 |
| Standard | NIST-Traceable |
| Storage Temperature | 15 – 25 °C |
This case includes 18 bottles of 100ml pH 4.01 calibration solution.
Once opened, close the bottle immediately after use and do not return used liquid to the bottle, as this can introduce contamination and affect calibration accuracy.
Simply immerse the probe—such as the Aqua Master Tools S300 Pro 2 pH Electrode—in a small amount of the pH 4.01 solution and adjust your meter until it reads 4.01. Rinse the probe with clean water afterward.
Keep bottles sealed and store them between 15-25°C, away from direct sunlight and extreme temperatures, to preserve accuracy until use.
pH 4.01 calibrates the acidic end of the meter's range. Pairing it with Aqua Master Tools pH 7.00 Calibration Solution lets you perform a two-point calibration for the most accurate readings.
For frequent or commercial use, a bulk 100ml case typically offers more solution per dollar than individual 20ml sachets, while still maintaining the same NIST-traceable accuracy.
Our specialists are happy to help. Call us or send a message and we'll get back to you within one business day (most of the time within a few hours.)
Equipping home growers, craft producers, and commercial operations across North America since 2016.
