Ok... So we had yellow mustard algae. The water was cloudy, there was yellow climbing the walls, and spats of yellow "gunk" throughout the floor of the pool. We pulled the stairs out and cleaned and scrubbed them. We slammed the pool for about 11 days (continuously vacuuming and scrubbing) and there was still yellow going up the walls and the water was still cloudy. My husband purchased "yellow out" from Leslies. He raised the pH to the recommended level and used the "yellow out". Within 24 hours the yellow was gone but it was still cloudy. So we continued to SLAM for about 4 more days until the water was clear and the overnight FC test was achieved. The pH was low so we raised it. Within 2 days, the pH was low again. We raised it again. The water became cloudy again and there are spats of gunk (can't tell the color) on the floor again. And the pH is low again. Any ideas or suggestions? Do we need to SLAM again first, then worry about the pH? Starting to feel lost.