Been three years since posted but the chlorine demand is back. Inground-DE-Vinyl- 23000 gal .Started out season good but now cannot get a FC reading above .5 .Eating chlorine at rapid rate .Last readings 7.0 PH ,.2FC,.2 CC,138 Alk, 80 cya, 258 hardness. Had chlorine demand test 4 weeks ago and came back 92 bags to add . I took option of partial drain and took water down 15 inches. Still same issue but new chlorine demand now says 33 bags. Water is perfect clear and has been . Options:
Do teh 33 bags but what type of shock ????
Do partial drain and another test and then shock? What type of shock?
swithch to Pristimne Blue ?
Fill in pool ?
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