I opened my pool late this year as usual. Of course, I had a very green pool. I immediately put in 4 gallons of 12.5% shock and filled some socks with stabilizer to get my CYA up to 40. My PH was over 8.0 before I added shock, so I added a gallon of muriatic acid as well. The water color changed overnight to a light green. I began checking the FC often and keeping it at 16 or above. Over the next two weeks, in spite of brushing twice a day, backwashing, and maintaining the FC, nothing changed. I remembered a bit of advice from another, now defunct, forum. That advice was basically the same SLAM advice, except the FC level advice was to keep it over 25. I just did that on Friday. This morning, my water is almost clear. I'm thrilled about that, but wonder why my experience would be any different than most others.
SLAM number for FC
- Thread starter beaverplt
- Start date
- Jun 24, 2021
- 16,289
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
The SLAM levels are set so that they do not damage pool/equipment or harm people. At SLAM level there is sufficient HOCl to kill algae. Any higher is unnecessary, doesn't make it go faster, and it can degrade equipment and is not safe for people.
Thanks for the fast reply. I was going on two weeks with no change (or so it seemed). Is that normal?
How sure are you on the CYA number? Assuming it didn’t come from a pool store?
I haven't been to a pool store in over 15 years. I should probably add one or two pool stories to that forum.
I did the test again this morning.
I did the test again this morning.
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Pool was much clearer this morning. But, with the clearer water, I see another problem forming. In a couple of those hard to brush areas, there is some scale building up. I brushed as much as I could off, but some is pretty stubborn. I've used a stiffer brush in the past, Any other suggestions?