Long question. Sorry. I just opened my pool but let it sit for a week because we had constant rain storms. When I took the cover off 3 days ago it was was green and foamy so I added shock, algaecide and the last little bit of metal control and let it sit. 2 days ago it looked like it had cleared up except for some remaining brownish green colored algae spots on the bottom. Yesterday morning when I tested the pool it was still low on chlorine so i added the recommended amount of shock again and scrubbed the algae off the bottom. That evening I tested the pool and it was still low on chlorine, and the pH and Alkalinity were really high and the water was cloudy. I added the recommended amount of \\\’pH down\\\’ (aka sulfuric acid). This afternoon, I tested the pool and it still had a high pH and Alkalinity level and low chlorine levels and the water is still cloudy. What should I do? Should I also add some more metal control too?

Question:

Long question. Sorry. I just opened my pool but let it sit for a week because we had constant rain storms. When I took the cover off 3 days ago it was was green and foamy so I added shock, algaecide and the last little bit of metal control and let it sit. 2 days ago it looked like it had cleared up except for some remaining brownish green colored algae spots on the bottom. Yesterday morning when I tested the pool it was still low on chlorine so i added the recommended amount of shock again and scrubbed the algae off the bottom. That evening I tested the pool and it was still low on chlorine, and the pH and Alkalinity were really high and the water was cloudy. I added the recommended amount of \\\’pH down\\\’ (aka sulfuric acid). This afternoon, I tested the pool and it still had a high pH and Alkalinity level and low chlorine levels and the water is still cloudy. What should I do? Should I also add some more metal control too?

Answer:

This is a pretty common issue when starting up a swimming pool with an organic load. Even though you have cleared up the swimming pool, there are likely still contaminants that you cannot see that are consuming the chlorine that is added very quickly. The organic load in your pool has increased the chlorine demand to the point where you are adding more than you are used to adding to establish a free chlorine level. You might consider a granular chlorine shock (there are many shock types) with lower pH and not further increase the pH with your chlorine additions. Liquid Chlorine, calcium hypochlorite and others have a high pH so will increase the pH (and typically alkalinity) when added. Dichlor or a more acidic chlorine will have a lower pH and should at least prevent the pH from climbing higher as you add chlorine.