Sounds like you're doing things right.
One thought I just had.....Have you ever added any nonchlorine shock like Leslie's Fresh N Clear? Because that will read as CC.
Question about slam
- Thread starter kjfin
- Start date
One thought I just had.....Have you ever added any nonchlorine shock like Leslie's Fresh N Clear? Because that will read as CC.
No, but the pool was closed with antifreeze in the lines if that matters. And, I had some chlorine tabs in the chlorinator just prior to getting my TF-100 and learning about the SLAM process. They were only in the chlorinator for a few days and have been removed for just over a week. I'm probably about 12 gallons of 10% liquid chlorine into the SLAM with a CYA of 60.
It was just a passing thought, so I thought I'd ask.
I've read about antifreeze creating a bunch of CC, but zero firsthand experience with the stuff. It doesn't freeze where I live. We hardly even see frost.
I'll just continue to SLAM and see if the gray dust goes away. It's a million times better than it was, just that little bit left but none in spots big enough to see with the eye, only when brushing I see the cloud appear at times.
- Jun 8, 2019
- 4,578
- Pool Size
- 20000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If it doesn’t, you could do a deep clean of the sand filter.
Even though it was new in the fall?
- Jun 8, 2019
- 4,578
- Pool Size
- 20000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Depending on how cloudy it was in there, there could be stuff the backwash doesn’t get out. I deep cleaned mine in the late summer with removing all of the sand to inspect the laterals, and I did it again in spring - still got more out in spring. (Not nearly so much, mind.)
Probably not an issue with a newer filter and sand, but just thought I’d suggest it
Probably not an issue with a newer filter and sand, but just thought I’d suggest it
Depending on how cloudy it was in there, there could be stuff the backwash doesn’t get out. I deep cleaned mine in the late summer with removing all of the sand to inspect the laterals, and I did it again in spring - still got more out in spring. (Not nearly so much, mind.)
Probably not an issue with a newer filter and sand, but just thought I’d suggest it
If my SLAM target is 24, I understand that I want to keep my FC as close to that as possible. But, at what lower than that level will algae still be there or not killed by the chlorine? Is there a definite window I should be in for the SLAM?
- May 3, 2014
- 59,324
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Each time you test FC, you raise it back to your SLAM level FC. Test and add several times per day.
That's what I'm doing. The pool is looking great and just trying to get the final bits of gray dust cleared up when brushing. Still confused as to how long it might take though. Started on May 18 with just a few gallons of liquid chlorine and got my TF100 kit a few days after to officially be able to test correctly and SLAM.
- May 3, 2014
- 59,324
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
So you are a week or so into the SLAM. A sand filter is the slowest to clear the pool. Keep at it.
In fact, the water is actually so clear now that the water ripples from brushing cause me not to be able to see the dust if there's some or none at all.
The answer is simply not that black and white.
The SLAM value for your pool is 24. Then as you go above 24 you start to waste FC and you start to move into a zone where some damage COULD occur to your pool. Notice, that is not a guarantee of damage but that it could occur. More likely simply a waste of chlorine but regardless, you want to be at 24.
Now, as you start to allow FC below 24. you are entering an area where the FC is no longer as fast acting and effective. Will the FC still work at 22? Of course.
Will it still work at 20? Yes. How about 16? Yes, but now slower still. Even down to 3-4 FC there is some killing power but you may not be able to kill the algae as fast as it can grow.
So, what is the "definite" window? There isn't one. That SLAM value is a number that is pretty close to ideal and you would be performing the SLAM incorrectly if you went wa-a-ay above it or wa-a-ay below it
Testing often and replenishing back to 24 ppm will make the SLAM successful. Stay as close to that as practical.
Ok, thank you!
n fact, the water is actually so clear now that the water ripples from brushing cause me not to be able to see the dust if there's some or none at all.
The only other place algae could be that I can't scrub is under the 2 main drain covers. They are too deep to get to and too cold to get in the water anyway. Do you think I am ok in not being able to get to them to scrub under?
- May 3, 2014
- 59,324
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
If you still have dead algae on the floor of the pool, the water is not clear. Just stay at it. Brush. I would not worry about the drain covers.
Ok, one more question.... brushing the dust gets everything stirred up into the chlorine obviously. But my question is....does the chlorine burn up the algae dust and it disappears? Or does it kill the algae into stuff I can't see and have to vacuum? By looking at the pool there's no dust to see to vacuum so there's no way to be effective. If it disappears by stirring up while brushing, then there's obviously a visual cue.
- May 3, 2014
- 59,324
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
The dead algae gets pulled to the filter for removal. Vacuuming is an important part of this process if you do not have a pool cleaner.
Is the gray dust I have been seeing dead algae or.......almost dead algae? I'm new to all this and just trying to learn.
I suspect not. Chlorine is an oxidizer. So is fire. But no matter how hot you burn some plant matter ( wood, algae) there will always be some ash left. You could put a blowtorch to some wood ash and end up with hot ashes. You could empty a barrel of chlorox into the pool and there would probably be some residue left from the algae.
Vacuum first. Sneak up on it and let the suction pull the dust into the vacuum and then move superslowly forward to get the next bit without creating a pressure wave that scatters the dust. Then go back and brush and anything that was stuck to the walls or floor will be loosened and stired up to either get drawn in the skimmer or to settle out for you to vacuum up next time.