Milwaukee MC122 Digital pH Controller for Dosing Control in Aquariums and Industrial Applications

The pH Controller MC122 automatically monitors and fine-tunes your pH levels.

Just set your pH parameters and let the Milwaukee pH Controller handle the rest.

Scientific studies and industry reports consistently highlight the importance of precise pH monitoring in both aquaculture and hydroponics. Customer reviews of the Milwaukee PRO pH Controller emphasize its reliability, ease of use, and consistent performance in maintaining nutrient solutions and aquarium water. Popular applications include nutrient tanks, aquariums, and other controlled water systems, with users noting the controller’s ability to stabilize pH levels, reduce manual testing, and integrate smoothly with compatible dosing pumps.

The Milwaukee PRO pH controller is preferred by professionals and hobbyists who need to maintain precise pH levels on an ongoing basis. Common uses are nutrient tanks and aquariums.

Key Features

The Milwaukee PRO pH controller offers:

ACCURACY

The Milwaukee PRO pH controller delivers 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 the set point.

COMPATIBLE DOSING PUMP

Milwaukee offers the MP810 dosing pump for precise chemical dosing.

EASY INSTALLATION

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

DESIGN FEATURES

• Fast, easy-to-read results with a large digital LCD display
• Accurate to ±0.2 pH (0.0 pH to 14.0 pH) with user-selectable high/low set points
• Simple two-point calibration with manual trimmers for easy adjustment
• Gel-filled, double junction lab-grade pH electrode for low maintenance and high performance
• 6.5 feet probe cable for extra flexibility when testing
• 12 VDC power supply

USE AND CARE

pH meters often start performing poorly due to probe issues. The two main parts that cause problems are the glass sensing bulb and the reference junction.

SENSING BULB

The glass bulb loses sensitivity over time and will eventually fail, which is true for all pH probes.

REFERENCE JUNCTION

The reference junction is a small hole that allows the meter to compare the sample to a reference. If the junction becomes clogged, the pH probe will no longer function properly.

EXTENDING PROBE LIFE

You can extend the life of your pH electrode in several ways:

STORAGE

The pH probe must remain hydrated. Long periods of dry storage damage the probe’s sensitivity and may clog the junction. Store the probe in pH probe storage solution or calibration buffers—not tap or DI water. Keep the probe cap filled and tightened to prevent leakage, and store upright to minimize potential spills.

CLEANING

Residue from samples, especially those with organic material, can affect the sensing bulb and clog the junction. Regular soaking in cleaning solution is recommended.

CALIBRATION

pH sensing bulbs lose sensitivity over time. Regular calibration ensures the Milwaukee PRO pH controller maintains accuracy, especially after cleaning or long-term storage.

To complement the automated monitoring and control provided by the Milwaukee MC122 pH Controller — a compact controller capable of maintaining pH within a defined set point range and activating connected dosing equipment upon deviation — consider additional water chemistry control and measurement tools that enhance your process control workflows.

The Milwaukee MP810 Dosing Pump pairs seamlessly with the MC122 controller to automate acid/base additions for pH correction, supporting stable nutrient or aquarium environments. For continuous dissolved oxygen tracking that complements pH regulation in water systems, the Dissolved Oxygen Meter with Calibration delivers precise DO measurement with onboard calibration support. Additionally, the Portable Water Quality Meter provides rugged, field‑ready multi‑parameter analysis — including pH, conductivity, dissolved oxygen, and temperature — enabling comprehensive aquatic quality assessments across laboratory and outdoor applications.

Q&A

What range of pH can the MC122 controller handle?

The MC122 controller has a control range of 5.5 to 9.5 pH.

How accurate is the Milwaukee PRO pH Controller?

It is accurate to ±0.2 pH when calibrated using the two-point manual method.

Can I use any dosing pump with this controller?

While the controller can work with other pumps, Milwaukee recommends the MP810 dosing pump for optimal compatibility.

How should I store the pH probe when not in use?

Store the probe hydrated in pH storage solution or calibration buffer, with the cap tightened and upright to prevent leakage.

How often should I calibrate the pH controller?

Calibrate regularly, especially after cleaning or prolonged storage, to maintain accuracy.