It's a above ground pool. 18'x 48" Intex Ultra Frame, 6,423 gallons, Pump is Krystal Clear model 635T, filter cartridge, filters 1500 gallons an hour. The only chemicals that have been added are; HTH 1' CHLORINATING TABLETS in a floating holder. Tested the water the next day with AQUACHEK Test strip. Strip showed little chlorine, high PH, High Alkalinity, low stabilizer. next we added a gallon of MURATIC ACID, waited 24hrs & tested the water again. All readings were the same, except PH was now normal. Added I pouch of SHOCK 'N SWIM. Tested the water later in the evening. All readings were back to the original numbers. Added 1/2 gallon of MURATIC ACID waited several more hrs, tested again. PH high, showed little Chlorine, alkalinity still high, low stabilizer.
Thanks for all the help!