December 2, 2022


Search for a Red Tide Remedy

Barbara Miracle | 5/1/2005
For much of the year, the white sandy beaches of Florida's Gulf Coast are picture-perfect. But during some days or weeks, the beach is rancid and beachgoers encounter vistas of dead fish.

The culprit? Red tide. As defined by the Florida Fish and Wildlife Research Institute (FWRI), the phenomenon is a higher-than-normal concentration of a microscopic, plantlike organism called Karenia brevis. The organism produces a toxin that can affect the central nervous system of fish. At high concentrations (called a bloom), the organisms may discolor the water and cause respiratory difficulties in humans.

"Red tide toxin will make you sick," says Bob Rigby, a passionate crusader for cleaning up Florida's inland and offshore waters. For the past 11 years, Rigby, 66, has been working on developing a chemical compound to control the organism that causes red tide.

Rigby, former owner of a heavy-equipment construction company and inventor of a machine that cleans gutters and removes roadway pollutants, admits that he doesn't have a scientific education. But he's come up with a chemical concoction he says will kill the organism. It takes about a drop to treat one gallon of water, he says.

"My intent is to treat it offshore where the bloom develops -- kill it there," he says.

Although red tide has been found worldwide, the Florida type is found only in the Gulf of Mexico. Blooms found off Florida's Atlantic Coast most likely originated in the Gulf and were carried by the Gulf Stream currents around the peninsula.

When Rigby, who lives in Nokomis, couldn't get local marine research laboratories to test the compound, he turned to nearby Venice High School. With the help of the FWRI, which provided samples of the red tide organism, and two grants of $1,000 each from the Venice City Council, the high school students have been testing Rigby's formula.

So far, the young researchers have found Rigby's formula -- which he won't explain in detail because of intellectual property concerns -- to be effective in very small concentrations in killing the red tide organism. They've also found that it won't harm fish. And what about the formula's effect on humans? It hasn't been tested, but Rigby quips, "I've bathed in it before."

Scientists at more established venues are also studying red tide. Researchers at Sarasota's Mote Marine Laboratory have filed a patent application for controlling the growth of algae blooms generated by Karenia brevis by applying seawater containing low levels of dissolved ozone directly onto or under the surface of water containing the blooms. And FWRI is conducting an in-depth study of Karenia brevis' occurrence and dispersal as well as a volunteer monitoring project.


The Red Tide Alliance website has links to the current status of red tide blooms in Florida and historical maps of red tide activity. There are also health tips and a red tide information kit designed to help businesses explain red tide to tourists and other customers. The alliance is a public-private partnership of the Florida Fish and Wildlife Research Institute in St. Petersburg, Sarasota's Mote Marine Laboratory and Solutions to Avoid Red Tide (START), a grass-roots citizens organization.

Tags: Environment

Florida Business News

Florida News Releases

Florida Trend Video Pick

Check out this Miami Beach art exhibit made by chimpanzees
Check out this Miami Beach art exhibit made by chimpanzees

Take a look at the ‘@rt by Chimps’ exhibit at the New World Symphony Center in Miami Beach. Chimpanzee artists painted 15 canvases that were up for sale during the fundraising event and all proceeds from sales go toward the Save The Chimps sanctuary.

Video Picks | Viewpoints@FloridaTrend

Ballot Box

Is it your opinion that the coronavirus pandemic has ended in the United States?

  • Yes
  • No
  • Unsure
  • Need more information
  • Other (Please share your comments in the comment section below)

See Results

Florida Trend Media Company
490 1st Ave S
St Petersburg, FL 33701

© Copyright 2022 Trend Magazines Inc. All rights reserved.