Tested pool and most stuff looked good but cya was over 80, so based on that I replaced about 4000 gallons of water. Now I heard or read u need to wait for about 7/10 days and test again. My question, will it be higher or lower right after replacing the water or after waiting time period. Just for heck of it I tested today (3days after) and had about 47 reading. Should I expect it to go up or down from there, thanks.