Oxidation-Reduction Potential (ORP)
A measure of the oxidizing or reducing capacity of water, used to monitor sanitation strength in reservoirs, irrigation lines, and water treatment systems.
Oxidation-Reduction Potential (ORP) measures the tendency of water to oxidize or reduce other substances. It is reported in millivolts (mV) and is commonly used to monitor the activity of oxidizing sanitation methods in irrigation water.
In indoor cultivation, ORP can help growers understand whether a reservoir or water treatment system has enough active oxidizer to suppress biofilm and pathogens in tanks, filters, emitters, and irrigation lines. It is most relevant when using compatible sanitation products or water treatment equipment.
Common uses:
- Monitoring sanitation strength in reservoirs
- Checking whether oxidizing treatments remain active over time
- Comparing water quality before and after treatment
- Detecting when organic load is consuming sanitizer
ORP is not a direct measurement of a specific chemical concentration. The reading is affected by pH, temperature, organic matter, dissolved minerals, and the sanitizer being used. Always interpret ORP with the product label, water chemistry, and crop safety in mind.
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