Evaluation of a Copper Based and Peroxide Based Algaecide for Treatment for Controlling Harmful Algal Blooms in a Recreational Lake

The frequency and intensity of harmful algal blooms is increasing posing a significant risk to surface water used for drinking water and recreation. All algaecide treatments were effective at reducing cyanobacteria within two days of application (p < 0.05). Overall, the most significant reductions in cyanobacteria content occurred with full dose of CutrineUltra and remained at less than 600 cells/mL by day 14. Quarter doses of both algaecides exhibited a rebound in cyanobacteria levels between day 7 and 14, indicating that additional treatments would be needed. Extracellular microcystin concentrations were higher on day 2 for PAK-27 treatments, by day 7 for CutrineUltra and full dose PAK-27 + 5 mg natural organic matter.