Fighting Red Tide with Clay Flocculation

University of Southern Florida (UCF) professor Kristy Lewis and her team think they figured out how to mitigate the spread of red tides by using clay flocculation, “which is really just a powdered clay put into solution and sprayed on the water,” she says. “The clay is positively charged, and it attracts the negatively charged red tide cells, removing them from the water.”

“It’s been used to treat harmful algae blooms in Southeast Asia for years, but it’s never been approved for use in the US,” she says.

Her research team has been experimenting for five years in the lab, on benchtops, and in tanks. In February, they took the test to natural water for the first time on an active red tide in Sarasota Bay. They ran the experiments for 48 hours, and Dr. Lewis says the results show that the powdered clay removed the red tide in the areas they tested.

Christy Kern, Fox 35, Orlando, FL
Tom McReynolds
Kyle Lansing

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