I am thrilled to find this site! I am a chemical engineer and find pool maintenance mind-boggling! We have started with a small (3500 gal/14 ft) above ground pool to see if we want to go in ground in the future. We filled the pool with well water - brown due to hi iron (very hard water in this area). Have been using the filter & sump pump for days. Water is now clear with minimal "slug" on walls & floor. We are wiping that off. Did first water test showing, no Cl, pH = 8.5, alkalinity = 250. After reading LOTS of comments I am afraid to start adding chemicals - what do I do next? Help please.