Accurate. Simple. Reliable. 24/7 pH Control.

The Milwaukee MC122 PRO pH controller lets you measure and adjust pH levels automatically.

The MC122 controller automatically monitors and fine-tunes the pH levels. Just set your pH parameters and let the MC122 do the rest. The controller provides a control range of 5.5 to 9.5 pH with alarms that activate when readings are higher or lower than set point.

The MC122 is preferred by people looking to dial in their testing program when they have an ongoing need to maintain levels. Common uses are nutrient tanks and aquariums.

What People Are Saying

"I run this unit 24/7 and have not had any problems for the past two months. It keeps my fish tank CO2 injector running perfectly and puts my mind at ease regarding overdosing."

"I've been using this controller for two years to monitor and adjust pH of hydroponic nutrient solutions. Still using the original probe and it rarely needs calibration."

"Using this as a pH controller for a calcium reactor on a 105 gallon reef tank ... I recommend this to any serious reefer."

Features

Accuracy

The Milwaukee PRO pH controller offers an accuracy to ±0.2 pH with two point manual calibration.

Automation

The controller provides a control range of 5.5 to 9.5 pH with alarms that activate when readings are higher or lower than set point.

Compatible dosing pump

Milwaukee offers the MP810 dosing pump

Easy installation

The pH Controller comes with a complete mounting kit including a probe holder.

Design features

• Fast easy to read current results with large digital LCD readout
• Accurate to ±0.2 pH
• Simple two-point calibration for increased accuracy with manual trimmers for easy adjustment
• 5.5 to 9.5 pH alarm set point range is easily accessible on the front panel
• Alarm activated when reading is above or below set point
• Comes with full mounting kit including probe holders
• Lab grade, double junction, gel filled probe designed for low maintenance
• 6.5’ probe cables for extra flexibility
• 12 VDC power supply
• Small footprint of 5.9 x 3.2 x 1.35”
• Lightweight monitor at approx 6.3 oz.

Use and Care 

pH meters usually start performing poorly because of problems with the probe. The two parts of the pH probe that cause problems are the glass sensing bulb and the reference junction.

Sensing bulb

The glass bulb loses sensitivity with use and will eventually fail. This is true of all pH probes.

Reference junction

The reference junction is a small hole that allows the meter to compare the sample to a reference. The reading is generated based on the electrical difference between the sample and reference. If the junction hole gets clogged, the pH probe will no longer function.

You can extend the life of your pH electrode in the following ways.

Storage

The pH probe needs to be kept hydrated. Long periods of dry storage will damage the sensitivity of the probe. Allowing the probe to dry out may also result in the junction hole getting clogged.

Store the pH probe in storage solution MA9015.  Only use tap water short-term if MA9015 is not immediately available and NEVER store in distilled Water (DI) or Reverse Osmosis (RO) water. This will damage the sensitivity of the probe.

This best way to store the probe is with the probe's cap filled with MA9015 Storage Solution and the cap tightened to prevent leakage. It is also recommended that to store the electrode upright to further reduce the potential for leakage.

Cleaning

Residue from the sample can impact the sensitivity of the sensing bulb and block the junction. This is especially true if the sample has a lot of organic material. We recommend regularly soaking the probe in MA9016 Cleaning Solution for about 20 minutes.

Calibration

The pH sensing bulbs become less sensitive over time so make sure that you are calibrating reguarly to keep your PRO pH controller accurate. Also, calibrate after cleaning or a long period of storage.