We’ve owned and managed our pool (22k gallon gunnite with pebbletec finish) for ~15 years. Some years are great. Some are a real battle. The pebbletec finish is 3 years new for us, and we closed the pool last fall with what I suspect was the start of black algae. I came across this site and am excited to leverage the know how of the team as we open the pool and get it back to best working order.