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I wish I knew what redox potential (ORP) is!

At all times in the entire world, we have trading going on, and I don’t mean stock exchanges. I mean electrons! We can’t see it, but in the air, the water, the earth and even our bodies, we have ion swapping going on!

This happens because many substances lack electrons and other substances have more than they need. To make it all stable, things that lack electrons, oxidizing agents, constantly seek more. And things with extra electrons, reducing or anti-oxidizing agents, generously share their goodies.

So the oxidation-reduction potential (ORP) of a substance, also known as redox potential, tells us to what degree it can reduce or oxidize another substance. You can measure it with an ORP meter, which will give you a reading in millivolts.


redox potential
Courtesy of American Aquarium Products

Positive readings of ORP or redox potential indicate a lack of ions, which gives you an oxidizing agent. And the bigger the reading, the more likely the agent can oxidize another substance.

A negative reading, on the other hand, means you have a reducing agent with a surplus of ions. Again the bigger the reading, the more this agent can reduce another substance. And there you have it the redox potential !

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