This is a fantastic resource and a great place to turn when you need help, I recommend it often.
I started a SLAM process on July 16. My CYA was at 0 (another post). I added enough powder to bring the CYA to 40 and confirmed with multiple tests. I have been in continuous SLAM mode since July 16th (10 days). I am keeping the Cl at 19 or higher, as indicated by PoolMath for CYA of 40. I have read the SLAM process multiple times and am familiar with the concept, keep the Cl at or above SLAM level until the three criteria are met. So far for the OCLT I am missing 2 of the three criteria, at least the water is clear.
My pump is a variable speed, so it is running 21 hours at 25% and 3 hours at 75% except when I turn it up for Cl additions and testing. My routine has been:
First thing in the morning at 7 am: Run the pump on high, test - add Cl to get about 25
When I get home (6-7 pm): Run the pump on high, test, add Cl to get about 25
Test at about 9 pm to confirm the Cl level before going to bed.
The Cl usually tests at about 16-19 at the end of the day.
The problem is that the CL consumption is getting worse. Last week, I was losing 1 -1.5 ppm overnight, but not passing the CC test (1 - 1.5 ppm). Now, for the last 2 nights, I have lost 6 ppm each night. I also lose about 6 ppm over the course of the day as well (7 am to 6 pm). The CC are staying at between 1.0 and 1.5.
Nothing unusual is going on in the pool, the skimmer baskets are empty (no dead rats, been there, done that). My only guess is that I need to raise the CL higher, like to mustard level for a while and try that. Is this a Cl resistant strain, mutant algae, or (more likely) am I missing something? Or does it sometimes just take this long, and this much bleach? Thoughts?
CC: 1 - 1.5
pH: Unknown (was 7.2 at the start)
Temp: 84 (finally!)