SLAM'd my pool last wednesday (approx 8 days ago). Felt it was an opportune time because the remnants of the hurricane was hitting our area and no one would be in the pool for several days anyway. Applied enough LC to raise to prescribed 20 FC level based on the chart. In fact it was closer to 25 but I realized two days later that I exceeded the 20 because even though my chlorinator was off it still depleted tabs in the cartridge. Anyway, ran OCLT Saturday night in to Sunday morning and everything was fine and looked good. Had guests over Sunday which made me nervous because I was still near the 20 FC level, but we survived. It is now Thursday. Since Sunday, I never let the FC go below 11. Used the pool Sunday, didnt use Monday all day stayed covered with solar cover, used it Tuesday. Wednesday we would be away so didnt use, and stayed covered, but knowing I had guests coming Thursday I dumped 3/4 gallon of LC Wednesday morning just in case. Thursday morning while still covered I checked FC at 15, never looked past the cover. Figured Id let in get to normal level over the next few days. A few hours after testing early Thursday morning, I uncovered and I had visible algae. Nothing crazy (but it wasnt terrible before I SLAM'd either), but still visible. As I said in title. Really frustrating that I cant get more than a week out of the SLAM. LC isnt cheap and not readily available around here. What is going on here??? Any helpful suggestions appreciated.
Really frustrated
- Thread starter wmmihail
- Start date
You are stopping the SLAM before meeting the ending criteria. Your cover also may be introducing algae if it wasnt cleaned.
- Jun 22, 2014
- 52,017
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
My first area of concern would be the cover. Pool covers of any type seem to retain algae spores, so if you didn't clean it thoroughly during the SLAM, it's possible the water was good until the cover went back on.
Well saying I stopped the process before it was finished, I dont agree with. What is the marker for a successful process? OCLT, isnt it? Is there something else I missed?? I passed the OCLT criteria. On the other hand, the cover is something I thought of. I dont see any practical way to clean a cover off the pool but the cover was on during the entire SLAM process. I thought that might suffice. Lastly, my phosphates have been high for the last few years. I reduced somewhat early this year by adding fresh water. But I have read many threads here that phosphates are nothing to be really concerned with.
The other two criteria are crystal clear water and a CC measurement of 0.5CC or less, all at the same time as passing an OCLT. Maybe you did those things but didnt add that to the thread? If so, then the cover is what I would into more.
Thanks. Yes, met that criteria as well. While the water before the SLAM was not "crystal" clear it was what I would call clear despite the presence of algae, even after brushing it. After the SLAM the CC was good and the water was visibly clearer, it did sparkle in the sunlight. LOL. Additionally, there was a noticeable difference in the feel of the liner under my feet. less slippery.
Sorry, I mean crystal clear water means no algae dead or alive. In fact, thats what the SLAM instructions use as the criteria. If there was visible algae, the SLAM wasnt completed yet.
I stated the water before the SLAM was not crystal clear. Crystal clear seems a bit subjective to me, how is that defined? I used the term - the water sparkled when I determined the SLAM was done. Might that not be the same thing? What's really frustrating is that in the last 2 years this has been an ongoing dilemma, never in the 10 years prior ownership of this pool have I had issues. And most of those 10 years I had a simple OTO kit and never exceeded 3-4 ppm total chlorine. I guess maybe ignorance was bliss back then but something has changed dramatically that even at 13 FC I cant keep algae out of the pool.
The requirement is:
- AND pool water is crystal clear with no visible sign of algae (dead or alive) on floor and walls
One thing that would help is to log your test results in pool math so you can see trends on whats happening. You can also share them on the forum.
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