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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 meter to a precise, NIST-traceable reference point in seconds, so every reading that follows can be trusted.
Each box holds 25 individually sealed 20ml sachets — enough single-use solution to keep meters accurate across an entire grow cycle without the contamination risk of a shared bottle.
Certified pH 4.01 formulation calibrates meters to a recognized national standard.
Box includes 25 individual 20ml sachets, enough to last a full growing season.
Individually sealed packs prevent contamination, so every calibration starts fresh and accurate.
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 Sachet | 20 ml |
| Sachets per Box | 25 |
| Standard | NIST-Traceable |
| Storage Temperature | 15 – 25 °C |
| Package Dimensions | 7.48 × 3.35 × 5.91 in |
Simply immerse the probe 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.
Most growers calibrate weekly, or any time readings seem inconsistent with expected values. Regular calibration keeps pH adjustments accurate.
No, each 20ml sachet is intended for single use. Reusing solution can introduce contamination and lead to inaccurate calibration.
pH 4.01 calibrates the acidic end of the meter's range. Pairing it with pH 7.00 lets you perform a two-point calibration for the most accurate readings.
Keep sachets sealed and store them between 15-25°C, away from direct sunlight and extreme temperatures, to preserve accuracy until use.
Each box includes 25 individual 20ml sachets, giving you 25 single-use calibration sessions for your meter.
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.
