Hi I have a 28 ft above ground sand filtered pool.We had a swamp land and now I have milk. I have had the water tested and they say it's fine except for the cya is non existant we have put in over 8lbs of stabilizer and it still reads zero.Everything else is fine for the longest time it wasn't holding chlorine but now it's at schock level and hasn't come down,as I have been trying to schock it repeatedly to try and clear it up.
Do you have any suggestions on what I could be doing wrong . Ph and Alk are in the normal range FC is at the max and the CYA is still zero. Any suggestions would be appreciated.