I'm absolutely fascinated! For years we've railed against pool stores selling "Phosphate Reducer" and worse, annual contracts for it--as mainly a waste of money and had scads of pools with "high phosphate" levels that never had a problem.

Now we have a workable, truly testable hypothesis: that when a pool is suffering from Mustard algae, phosphate reduction may actually BE the way to finally solve it! If this turns out to be true, we will have another simple, clear-cut tool in our tool-box!

Since my pool is still a skating rink under the cover (despite warm days we are still waking up to the 'teens') I won't be much help in testing!