Omni pH Decreaser
Omni pH Decreaser is our favorite and highly recommended pH decreaser. This product it perfect for spring and summer to prevent or reduce algae blooms. This granular chemical designer to slowly lower the pH of your pool/pond water is safer than liquids acids such as muriatic (hydrochloric) or sulfuric.
For dealing with a string algae bloom; first harvest all the string algae you can yourself (its wonderful for composting), then lightly sprinkle the recommended dosage for your NSP (based on gallon size) directly on the algae on rock surfaces and swim walls. The offending algae will die and look “dusty” and should filter and clear out through the skimmer and water circulation within a day or so. Give the surfaces a gentle scrub if needed to loosen the dead algae.