Split by moderator from HERE. Check your facts before posting in someone else's thread again. jblizzle
Your PH is pretty good as long as it stays 7.2 - 7.6 , other wise chlorine becomes ineffective with higher P.H.'s Yes Shock your Pool `Then Let it run for 24 hours at least it will be a day or two before you get true readings after shocking a pool- so be patient and wait, then follow rules for balancing water. i.e.
Alk 80- 120, vinyl can go up to 150. If you add CYA you must divide the CYA ppm by 3, subtract that from your alkalinity and thats your true Alkalinity ppm.
Calcium 200 - 400 regardless of liner type. its all about your waters Saturation index in the end.
CYA should be 30 - 60 ppm, some say 80 ppm is ok but more than that will once again stop chorine from doing it's job and you'll get algae etc..
Chlorine can be from 1-3 ppm even 5, if P.H is at good levels you'll be comfortable. P.H is what bothers people in the pool, not chlorine.
Any pool should have all its water filtrated at least once every 24 hours, maybe more with heavy bather loads.
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CYA is a useless product I believe. Only China makes it and they're lobbying to stop its import anyway.