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We support operations & licensed facilities with volume pricing, dedicated account managers, and custom equipment consultation.
A pH meter that hasn't been calibrated recently can drift silently off target, throwing off nutrient decisions before you notice anything's wrong. Bluelab pH 4.0 Calibration Solution solves this by giving your Bluelab pH Pen or meter a known reference point to calibrate against, keeping readings accurate and dependable.
Regular cleaning and calibration boost the longevity of your pH probes, and the pH 4.0 solution is a core part of that routine — a must-have in every grower's maintenance toolbox alongside Bluelab pH 7.0 Calibration Solution for standard 2-point calibration.
Sold exclusively in box-of-6 case packs, available in 250ml (8.4fl.oz.) or 500ml bottle sizes — choose the size that matches your usage and restocking needs from the size selector.
A known 4.0 pH reference point keeps your meter reading true.
Regular calibration and cleaning with storage solution keep your pH probe performing longer.
Available in 250ml and 500ml bottle sizes, sold by the case.
| Option | Volume |
|---|---|
| Case Pack | Box of 6 — 250ml bottles |
| Case Pack | Box of 6 — 500ml bottles |
It's a known reference solution used to calibrate your pH meter or pen, ensuring readings stay accurate over time.
Yes. Standard 2-point calibration uses both pH 4.0 and pH 7.0 solutions together to ensure accuracy across your meter's full range.
It's sold in box-of-6 case packs, available in either 250ml or 500ml bottle sizes.
Regular calibration helps extend the life and accuracy of your probe — check your specific meter's manual for a recommended schedule.
No — this solution is now sold exclusively in box-of-6 case packs, available in 250ml or 500ml bottle sizes.
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.
