pH meters

Checking freshly mixed nutrient solution or a separate water sample? The Milwaukee PH51 pH pen is a compact meter for liquids. It measures from 0.0 to 14.0 pH with 0.1 pH resolution. Calibration is manual and the electrode is replaceable. It is a complete meter, rather than a separate probe.

Mix the solution thoroughly and wait for a stable reading before making adjustments. Measure pH and EC separately: pH describes acidity, while an EC meter measures electrical conductivity. A pH meter cannot tell you how much nutrient you have added.

For direct readings, use a probe designed for the medium. The Aqua Master Tools S300 Pro2 substrate meter measures pH and temperature in soft, moist substrates and liquids. Its separate cabled probe helps you reach awkward measurement points. The meter has automatic two-point calibration and a replaceable electrode.

Do not push an ordinary water pen into soil. Keep moisture level, measurement location and method consistent. A reservoir reading, runoff reading and direct substrate reading measure different conditions; do not treat the results as interchangeable.

Need automatic adjustment as well as measurement? The Bluelab pH Controller Wi-Fi with dosing pump measures pH and doses through a built-in peristaltic pump. Select one control direction: raising or lowering pH. Wi-Fi lets you connect the controller to Edenic for remote monitoring and control.

This serves a different purpose from a handheld meter. Match installation, mixing delays and dosing settings to your reservoir and pH adjuster. Check installation and calibration before enabling automatic dosing; the controller still needs regular probe care.

Replacing a probe? Check the exact meter model, connector and application. The Bluelab pH probe for liquids and Bluelab soil pH probe are separate components for a suitable meter. The liquid probe has a BNC connector and a 2-metre cable. Choose the soil probe when you need a suitable probe for direct substrate readings.

The Aqua Master Tools pH electrode for P700 Pro2 is also a replacement part. Do not buy a separate electrode if you do not have a suitable meter. If unsure, ask us to check your current instrument and probe before ordering. Recalibrate the meter after replacing its probe.