I live in Spain and have an in ground tiled pool of 30,000 gallons. I have been looking at the forum for some time since I started having problems with algae and cloudiness. Have been using three effect granules between January and June and occasionally adding some acid to keep the PH down. I have a Guardex 4 in 1 test kit and the levels were all fine. All was good until I left the pool with some guests in the house for a couple of weeks.
They let the water level and Chlorine level get too low and so the pump wasn`t filtering properly and we had a green pool on my return. Started to put a lot of Chlorine tablets in the skimmer to get the Chlorine up and added some flocculant. things have improved but the water is still a bit green and not clear.
From the information on the forum I suspected that the CYA level was too high but could not test it. In order not to raise the CYA level by using the tablets started to add bleach to get the Chlorine level up to 3. Haven`t been able to shock as the have had a lot of kids staying who want to go in the pool every day. Have ben adding at least a gallon of bleach a day but the level is hard to keep up. Just got the water tested at the pool store with the following readings.
PH - 7.7
FC - 2
TAC - 1.5 (I think)
TAB - 3.4
Total Alkalinity - 80 ppm
CYA - 88
I think I need to lower the CYA and shock the pool which I can now do. Could you advise me please the best course of action.