Aqua Master Tools pH 4.01 calibration solution

pH 4.01 calibration solution from Aqua Master Tools in a 100 ml or 500 ml bottle. Together with pH 7.00 it lets you calibrate any pH meter at two points.

A pH electrode drifts slowly, even when stored well. That's why you calibrate your meter regularly: with daily use about once a month, and whenever readings look odd. Aqua Master Tools pH meters calibrate automatically at pH 7.00 and pH 4.01, so these two solutions are all you need.

How to calibrate well

Pour a little solution into a clean cup and calibrate in that, not in the bottle, so the rest stays clean. Rinse the electrode with demineralised water between the two solutions. Throw used solution away and never pour it back into the bottle. Close the bottle straight after use.

Technical specifications:

• pH value: 4.01 (at 25 °C)
• Volume: 100 ml or 500 ml
• Traceable to: NIST standard
• Storage: between 15 and 25 °C, bottle tightly closed
• Model number: AMT1103 (100 ml), AMT1303 (500 ml)

Frequently asked questions

Does it work with meters from other brands?
Yes, pH 4.01 is a standard value. Any pH meter that calibrates at 4.01 can be calibrated with it.

How long does the solution keep?
Keep the bottle tightly closed between 15 and 25 °C and check the date on the label. Never use solution that has turned cloudy.