Treating nutrients with algae blooms

By Betty Staugler, Charlotte County extension agent for the Florida Sea Grant Program

No, there’s not a typo in my headline. In fact, this technology is so cool, you really should continue to read. With all the bad press about algae, we often forget that it really can be beneficial. In fact, algae are responsible for much of the air we breathe, and they form the base of the food web upon which all life depends.

I suspect most readers are aware that algal blooms often occur when too many nutrients enter our waterbodies. With this understanding, a novel approach to remove nutrients from a waterway was developed and patented in 1980s by Dr. Walter Adey at the National Museum of History: The algae turf scrubber, or ATS.

The basic idea: Run the water across a shallow trough or raceway, upon which attached filamentous algae are allowed to grow. The algae treat the water by taking up nutrients, primarily nitrogen and phosphorus, as they grow.

Where does the algae come from? Provide the right conditions — sunlight, water and nutrients — and algae will establish naturally. What grows is the same green filamentous algae we often see attached to rocks and seagrass in shallow areas. Only in this case, instead of being a nuisance, it’s beneficial.