In StockpH Pen Calibration Fluid
£2.65
Online price · 10% online discount included
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Description
For use in calibrating all pH pens, pH Buffer 4 and pH Buffer 7 available in 300ml and 1l bottles.
Calibration of all measuring equipment should be performed weekly to ensure accuracy with critical nutrient solution measurements.
Key facts
| Type | pH buffer solution for calibrating pH pens |
|---|---|
| Buffers | pH 4 and pH 7 |
| Bottle sizes | 300 ml and 1 litre |
| Works with | All pH pens |
| How often | Calibrate weekly |
| Brand | Growth Technology |
| Sizes | 300ml / 4, 300ml / 7, 1l / 4, 1l / 7 |
| Category | Nutrient Management |
How to use
Calibrate your pH pen once a week, following the pen's own instructions, using the buffer or buffers it asks for. A pen that has drifted gives wrong readings for every feed you mix.
Questions
Do I need pH 4, pH 7 or both?
That depends on the pen: some calibrate at one point, some at two. Check the pen's instructions and buy the buffers it asks for.
How often should I calibrate a pH pen?
Weekly. All measuring equipment should be calibrated every week to keep nutrient solution readings accurate.
Growers’ guides
- How to Calibrate a pH Pen or Meter, Check EC and Store the ProbeHow to calibrate a pH pen in pH 7 and pH 4 buffer step by step, how often to do it, how to check an EC meter, and how to store and clean the probe.
- Hydroponics and Growing Terms Explained: A Growers' GlossaryHydroponics and growing terms explained in plain English, from EC, pH and PPFD to VPD, NFT and run-to-waste, with links to our full guides.
- pH and EC: Meters, Test Kits and pH Up/DownHow to test pH with a meter or a pH test kit, measure EC, read the makers' targets, use pH Up and pH Down, and calibrate and care for a meter.




