Hi, I have a 50K gallon in-ground plaster pool in central IL. Have owned for 12 years, learned a ton on this forum over the years and have had great results in the past. I use Menards liquid chlorine (12.5%), and the other common chemicals recommended on this forum.
Opened last weekend, a little dirtier/greener than some other years but not too bad. Vacuumed/filtered and adjusted pH for a couple of days, started SLAM 72 hours ago. Daily backwashes of our sand filter since opening. The water is still cloudy and has not progressed much at all, and some things seem different/off from previous years so thought I'd consult the experts on this forum.
Tests from just now:
Temp: 60F
FC: 16
CC: 2
pH: 7.4
TA: 50
CH: 90
CYA: 30
In previous years while SLAMming a lot of chlorine has been required, like 9-12 gallons on the first day, with regular doses on next 3 or 4 days to keep >= 12. This year the chlorine readings have been very high and have not gone down much at all. 6 gallons on first day, followed by 3 gallons 8 hours later and test was 20! Then it took almost 2 days before it got down around 12, added 2 gallons and it went right back to high teens and has only dropped to 16 this morning. I thought maybe my DPD reagents were expired, so I bought a new DPD kit, but the readings on the new one are exactly the same as the old. It has been cloudy/rainy so not losing much to sunshine, but with as cloudy/dirty as the water was I would have expected to need a lot more.
pH was low to start (7.2), added soda and it was just a bit high, added some acid on second day and it has been right in the sweet spot ever since. CH has always been low in this pool but I have not worried about CH or TA in the past until I got the water clear and dropped back down to normal FC range.
Robot vacuum has been running pretty constantly since opening and have brushed waterline and flat surfaces daily. The bottom is pretty clean.
Thoughts?
Opened last weekend, a little dirtier/greener than some other years but not too bad. Vacuumed/filtered and adjusted pH for a couple of days, started SLAM 72 hours ago. Daily backwashes of our sand filter since opening. The water is still cloudy and has not progressed much at all, and some things seem different/off from previous years so thought I'd consult the experts on this forum.
Tests from just now:
Temp: 60F
FC: 16
CC: 2
pH: 7.4
TA: 50
CH: 90
CYA: 30
In previous years while SLAMming a lot of chlorine has been required, like 9-12 gallons on the first day, with regular doses on next 3 or 4 days to keep >= 12. This year the chlorine readings have been very high and have not gone down much at all. 6 gallons on first day, followed by 3 gallons 8 hours later and test was 20! Then it took almost 2 days before it got down around 12, added 2 gallons and it went right back to high teens and has only dropped to 16 this morning. I thought maybe my DPD reagents were expired, so I bought a new DPD kit, but the readings on the new one are exactly the same as the old. It has been cloudy/rainy so not losing much to sunshine, but with as cloudy/dirty as the water was I would have expected to need a lot more.
pH was low to start (7.2), added soda and it was just a bit high, added some acid on second day and it has been right in the sweet spot ever since. CH has always been low in this pool but I have not worried about CH or TA in the past until I got the water clear and dropped back down to normal FC range.
Robot vacuum has been running pretty constantly since opening and have brushed waterline and flat surfaces daily. The bottom is pretty clean.
Thoughts?
So if you are familiar with and following the 
