Ok this is going to be somewhat long but I want to explain in detail. I have been taking care of my own pools for almost 40 years. I sort of do a BBB method but I use pool store chemicals. Chlorine, Soda Ash and Dry Acid. I do use a concentrated algaecide for opening and closing. I have had a 19 x 45 in ground vinyl pool for 6 seasons now. I live in NJ. I opened my pool as always the beginning of May. The PH was low and the people that open my pool put in what looked like about 5 lbs soda ash. After the opening I maintain my pool. In about 2 days my water was sparkling and ever so blue. The PH was still low and my chlorine was being eaten up like crazy. We initially shocked the pool same as always and I maintain with 3" tabs in the skimmer basket. 5 - 6 usually work in the early season. I know I needed to raise the PH so I went to the store to stock up on Soda Ash. Ultimately it took 25 pounds to get the correct PH. Now I also tried one of these liquid solar covers but I really don't think that caused the stains. If it did who would buy it. Anyway my sparkling blue pool was now a brownish green. The water was still clear. I then tried "Yellow Out" after raising the PH at the advice of the store. I also shocked again. No real improvement after about 2 days and I upped the 3" tabs to 8. I continued to add shock because in the past Chlorine would solve all color issues. I had good chemical levels this morning but the pool was only slightly better. I added another 5 pounds of shock and going to see what tomorrow brings. This is not algae as if cannot be scrubbed off. I haven't tried the vitamin C yet but I will tomorrow. It has also been raining a lot lately. All I can say is the steps are stained and most of the liner. The water is clear and does show blueness when I splash the water. I do not have a major test kit. In my almost 40 years never had the need for one. I have been using test strips the last 4 or 5 years and never had a problem. This is a first for me. I'm dumb founded. Maybe the over chlorinating will help over time but I'm wondering if I should use Yellow Out again or should I try something else. Thanks in advance.