So I just purchased my first home and it came with a pool. 1 month before we moved in I went over and got all the proper gating and safety lines put in place. At that time I noticed sand in the bottom of the pool and what appeared to be staining on the walls. One month later we moved in. I swept and swept the pool, followed the previous owners instructions and finally got frustrated and went to the pool store. The installers helped me trouble shoot and the following weekend I had my filter fixed and sand replaced. My water was now cloudy and slightly green/teal. Afterr searching the net I found this wonderful site. I shocked the pool, vacuumed the dead algae out and watched the water turn crystal clear. Now I am stuck, I received my TF 100 test kit 2 nights ago and have started my first offical slam. The reason I have to slam is because the walls are yellow. I have scrubbed and scrubbed with the chlorine at shock level for what feels like 2 weeks. I have tried the vitamin c test and the chlorine puck test. Nothing is working. I can scrape it off with my finger nail or a magic eraser that's it. There are trees that line the fence. I keep finding what looks like sand in the bottom of the pool but disappears with a sweep of the vacuum. The yellow is lighter closer to the water line and gets deeper the further down the wall. I also have slight yellow on the bottom. I am convinced it is yellow algae.
My current numbers are
FC being maintained at 28 ppm
CYA 70 ( I need to redo this test just to double check)
I did lose chlorine over night but it was only 2ppm. I will continue maintaining current slam levels until I pass the OCLT then bump up to MA shock per the directions. Shouldn't I see some improvement in the wall color or am I being to hasty.
Any tips, advice, encouragement and wisdom are very welcomed. I am becoming slightly discouraged and I am wondering if I am doing something wrong.