Milwaukee ORP Meter

Milwaukee Instruments ORP meters measure Oxygen redux potential in any body of water including aquarium.  The MW500 was a favorite among reefers now called MW500 and uses the Se 300 Replacement Probe.

Oxidation occurs in water when one cell takes ions from another cell and then causes that one to take from another, causing it to become a free radical, which cascades and the cells break down. The measurement of this process is called ORP (Oxidation Reduction Potential). We use the Milwaukee ORP meter to measure parameters in drinking water in which the theory is that a negative ORP will help maintain proper pH balance in the body.  Positive ions oxidize. It measures the tendency of a liquid if the liquid is an oxidative item or free radical.  The higher the number, the greater potential for harmful oxidation.  Many Kangen Water tester users use the Milwaukee MW500 ORP water tester to measure the output of the water filter, making sure there is a low pH.  When testing the water, they are testing the acidity or alkalinity of the water plus the oxygen redux potential.

In an aquarium now an ORP tester is good for the life of your fish and keeping good health.

High levels can make excessive corrosion, resulting in expensive repairs to your aquarium. This is one parameter that can be measured during the cleaning process for Enagic drinking water filters, swimming pools, pond water, and spa treatments. Corrosion can also be caused by incorrect pH levels and salt corrosion as well, so check out our pH testers and salinity refractometers now on sale. By the way, if you are an Enagic alkaline water dealer, check out for a brand new product.

The reason for using an ORP tester is depending on your low level you can kill lower level life forms such as bacteria. You can decrease bad bacteria in an aquarium or by lowering the ORP of the saltwater tank which works the same way in swimming pool or spa water.  This is a great swimming pool tester. It has been proven that the ORP will decrease the longevity of bad bacteria more efficiently than chlorine. In swimming pools, we try to maintain a pH of approx 7.2 through 7.6. This is ideal to decrease chlorine dissipation levels. You must maintain an ORP measurement above 700 mV to kill undesirable organisms.

Typical values mV
Properly chlorinated swimming pool > 700
Salt water aquarium ~ 350
Harmful to aquatic life > 400

Check out the MW500 meter.


Now Only

Milwaukee MW500 Smart ORP Meter

Milwaukee MW500 Smart Negative ORP Meter (Replaces SM500)

Milwaukee MC510 ORP Controller with Mounting Kit

Milwaukee MC510 ORP Controller with Mounting Kit

Milwaukee MA9015 Storage Solution for pH/ORP Electrodes (220ml)

Milwaukee MA9015 Storage Solution For pH/ORP Electrodes (220ml)

Negative ORP Tester MW500 ORP, Drinking Water Checker Kangen

ORP Testing is important for Water Quality. Kangen has recently been the buzz around the health and drinking water industry. If you are purchasing an ORP tester for this purpose get the MW500 negative ORP meter wholesale - see details.

Q: How do I calibrate the SM500 or MW500 meter?

A: The MW500 ORP meter is factory calibrated so you do not need to calibrate it. The MA9020 is a validation solution for positive (+) ORP.

Milwaukee ORP Meter MW500 Questions

We get a lot of questions on how to use the ORP meter, so for the SM500 or MW500 ORP meter, which is our most popular unit, we decided to answer some questions.

General setup Milwaukee MW500 ORP User Manual

User manual PDF MW500 negative ORP meter setup instructions

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