Hi all,
I've been leveraging knowledge from this website for the past few years with great results for my pool, but currently helping my parents work through an issue with their pool and a bit stumped. Here's the details/story:
~25,000 gallon above ground pool
sand filter (new sand last month, have been backwashing daily during recent few days)
~400k BTU gas heater
Illinois
FC-see below
CC- see below
CYA- 67 ppm pool store (~ 60 with taylor kit)
pH 7.0 (taylor)
130 TA (pool store)
200 hardness (pool store)
1995 phosphate (high I know, but not expecting it to cause an issue during SLAM..)
They had always used tri-chlor pucks to add chlorine and mostly tested with strips and a couple weeks ago they had a cloudy pool. Turns out CYA was at 180 ppm, so I had them remove 2/3 of water and they hauled in water with tanker. Brought the CYA down to 67 ppm. I then had them add 5 gallons 12.5% chlorine (25 ppm chlorine) and pool cleared up quickly. I then had them use cal hypo tablets instead for now. However, they didn't have a good test kit and pool started to turn a green over the next week or so. (A very clear emerald green, so I initially thought iron). I then had them get a Taylor K-2006 test kit and stock up on 12.5% liquid chlorine to do a proper SLAM and have the tools to maintain pool. I had them reduce pH to 7.2 (took 1 gallon HCl) and add 5 gallons 12.5% chlorine (25 ppm chlorine) and by the next day the green is clearing up, they continue to add more (multiple gallons, not sure exact amount) to keep chlorine high (never quite at SLAM though) and by day 2 the pool is crystal clear, but apparently not holding much chlorine (dropping from 20 to 10 during the day).
So this morning I tell them to up the liquid chlorine and add whatever it takes to maintain 25 ppm FC. Here's the results of the day:
morning- added 13 gallons 12.5% chlorine, wait ~45 minutes
FC 25.5, CC about 0 (I thought this was great!)
immediately added 2 more gallons to be safe
11:30 AM, retest after 2 hours since last addition, FC 17.5, CC 9, so added 4 more gallons
1:00 PM FC 10, CC 13 (they go buy more chlorine)
I then ask them to remove the large ladder they have with steps that 'hold' water and have sand in for weight, thinking maybe something is growing inside of them.
6:35 PM, stocked up on chlorine, add 33 gallons (this should be 165 ppm!!))
6:55 PM 8.5 FC, 25 CC
7:21 PM 7 FC, 31 CC
7:25 PM added 22 more gallons
7:50 PM 11 FC, 41 CC
At this point dad just went to the store and bought 120 more gallons of chlorine, it seems to be getting out of hand (already have added close to 70 gallons).. thoughts?? Pool has remained crystal clear and I don't thinks its ammonia, because chlorine doesn't drop to 0 FC on the order of minutes...
Thanks,
Bryan
I've been leveraging knowledge from this website for the past few years with great results for my pool, but currently helping my parents work through an issue with their pool and a bit stumped. Here's the details/story:
~25,000 gallon above ground pool
sand filter (new sand last month, have been backwashing daily during recent few days)
~400k BTU gas heater
Illinois
FC-see below
CC- see below
CYA- 67 ppm pool store (~ 60 with taylor kit)
pH 7.0 (taylor)
130 TA (pool store)
200 hardness (pool store)
1995 phosphate (high I know, but not expecting it to cause an issue during SLAM..)
They had always used tri-chlor pucks to add chlorine and mostly tested with strips and a couple weeks ago they had a cloudy pool. Turns out CYA was at 180 ppm, so I had them remove 2/3 of water and they hauled in water with tanker. Brought the CYA down to 67 ppm. I then had them add 5 gallons 12.5% chlorine (25 ppm chlorine) and pool cleared up quickly. I then had them use cal hypo tablets instead for now. However, they didn't have a good test kit and pool started to turn a green over the next week or so. (A very clear emerald green, so I initially thought iron). I then had them get a Taylor K-2006 test kit and stock up on 12.5% liquid chlorine to do a proper SLAM and have the tools to maintain pool. I had them reduce pH to 7.2 (took 1 gallon HCl) and add 5 gallons 12.5% chlorine (25 ppm chlorine) and by the next day the green is clearing up, they continue to add more (multiple gallons, not sure exact amount) to keep chlorine high (never quite at SLAM though) and by day 2 the pool is crystal clear, but apparently not holding much chlorine (dropping from 20 to 10 during the day).
So this morning I tell them to up the liquid chlorine and add whatever it takes to maintain 25 ppm FC. Here's the results of the day:
morning- added 13 gallons 12.5% chlorine, wait ~45 minutes
FC 25.5, CC about 0 (I thought this was great!)
immediately added 2 more gallons to be safe
11:30 AM, retest after 2 hours since last addition, FC 17.5, CC 9, so added 4 more gallons
1:00 PM FC 10, CC 13 (they go buy more chlorine)
I then ask them to remove the large ladder they have with steps that 'hold' water and have sand in for weight, thinking maybe something is growing inside of them.
6:35 PM, stocked up on chlorine, add 33 gallons (this should be 165 ppm!!))
6:55 PM 8.5 FC, 25 CC
7:21 PM 7 FC, 31 CC
7:25 PM added 22 more gallons
7:50 PM 11 FC, 41 CC
At this point dad just went to the store and bought 120 more gallons of chlorine, it seems to be getting out of hand (already have added close to 70 gallons).. thoughts?? Pool has remained crystal clear and I don't thinks its ammonia, because chlorine doesn't drop to 0 FC on the order of minutes...
Thanks,
Bryan
