Oxidation reduction potential (ORP) is one of the most overlooked factors influencing crop management in hydroponics. Terms such as pH, TDS and EC are comparable acronyms that are ubiquitous within the industry, with countless products available to monitor and influence their levels. But what exactly is ORP? And how can you use it to your advantage in simple, yet effective, ways?

  • It is a process by which an oxidizing agent adds oxygen to a solution and changes it. Chemically speaking, oxidation occurs when electrons are lost due to a reaction.
  • ORP is influential, and when used correctly, can contribute to the success of your crops.
  • Oxidation reduction potential describes a solution’s ability to oxidize the contents that comprise it. When oxidizers are used, solutions with a high ORP and high mV reading will result.
  • Solutions with a low or negative mV reading have a low ORP, and in hydroponics, this might indicate a lot of organic matter in your solution.
  • Solutions that maintain a high ORP are considered to have high killing powers, which translates to a sterile environment.
  • For those of you who prefer to grow in a sterile environment, maintaining a higher ORP will ensure best results. Because hydroponic growing involves a lot of recirculating water in which organic compounds are naturally and constantly developing, you will have to add oxidizing agents regularly to maintain a high ORP level.

The articles and excerpts below provide a thorough review of ORP.

CFU ORP Fusarium In Conifer Seedlings.pdf

Efficacy of Dissolved Ozone.pdf

Electorolysis and ORP.pdf

Electrolyzed Oxidizing Water On Diseases of Avocado.pdf

ORP to Help Reduce Pathogenicity.pdf

Using Oxidation Reduction Potential ORP For Water.pdf

ORP vs CFU Over Time.pdf

Orp Disinfection.pdf

Suslow ORP Disinfection.pdf

Suslow ORP Update.pdf

Suslow Survival at ORP Time to Kill.pdf