Talking Water Treatment

Talking Water Treatment

Talking Water Treatment

Paul Fisher, associate professor and Extension specialist in the Environmental Horticulture Department at the University of Florida, will discuss water treatment technologies February 25-27 at Pest & Production Management Conference (P&PMC) in Orlando. He previews the conference with us in a discussion about water treatment systems and new technologies.

What are the key factors growers must consider before deciding on a water treatment system?


There are a number of factors, such as installation versus operating cost, which products are best for removing biofilm and which technologies have residual effects through the whole irrigation system (such as chlorine) versus point treatments (for example, UV light).

All of the options can be successful for certain applications, but no one technology is always the best fit. Growers need to decide on the volume they want to treat, whether they are controlling alkalinity, EC or specific ions such as iron, or if it is the microbial quality of the water (pathogens, algae, biofilm) that is most important.

Filtration underlies all of the technologies for pathogen and algae control, because organic matter can deactivate sanitizing agents. Finally, water treatment is just one part of overall sanitation and IPM.

Growers are more concerned these days about costs. Financially, how much are we talking about for the installation of the various water treatment systems out there?

This can range from almost no installation cost, using an existing injector system, through to $100,000 or more once you consider improved filtration, redirecting plumbing and installing a system such as UV/Ozone. That may be quite a sticker shock, but if growers are treating high water volumes, then they may trade a higher initial installation cost for lower operating costs.

Some water treatment options have low installation costs, for example activated peroxygen products such as ZeroTol or Xeroton-3. Other technologies, such as copper ionization, have a higher initial cost but a low operating cost per 1,000 gallons treated. We will go through the costs of different options to help growers make that choice (at P&PMC).

Are most growers testing their water as regularly as they should be? What basic water testing methods do you recommend?

New onsite and laboratory tests are available to help growers manage nutritional and biological water quality in order to maintain crop health. For example, we have developed an onsite protocol for growers to plate out irrigation water on plastic films as an onsite method for testing bacterial load.

At the conference, we will demonstrate lab analyses (sampling, shipping and interpreting results); onsite analytical meters, kits and measuring protocols for alkalinity, pH, EC; ORP, chlorine and other sanitizing agents; bacterial load and pathogens; fertilizer injectors and leachate.

For more information on Pest & Production Management Conference (P&PMC), presented by Society of American Florists and Greenhouse Grower, visit

Want more from P&PMC speakers? Click the links below:

Jim Barrett on “Proper PGR Use”

Margery Daughtrey & Mary Hausbeck on “Disease Management Strategies”

Scott Ludwig on “Bio-Controls & Thrips Management”

Cristi Palmer on “Pests & Diseases”

Sonali Padhye on “PGR Developments”