Thanks! Yes-that was actually my plan, but it will have to wait until next summer due to multiple other expenses since moving into this house (sigh). But that will be happening eventually!
Pool not holding chlorine
- Thread starter DKJohnson24
- Start date
Poolnerdgrandma
Gold Supporter
- Sep 15, 2018
- 955
- Pool Size
- 17000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite Pro (T-15)
2 quarts sounds like a LOT to drop .2. Please double check those numbers before you put two quarts of acid in your pool.
- Nov 12, 2017
- 12,679
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
It does sound like a lot, doesn't it? But it's her TA (and her big pool). With a TA of 200 (assuming that's correct), she would need almost 2 quarts of 31% muriatic acid to go from pH 7.4 to 7.2...
One final clarification on SLAMing; this may be a dumb question…Am I supposed to be keeping it at full SLAM level until the end, or can I just elevate because chlorine loss is definitely slowing down?
- Jun 24, 2021
- 16,565
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
You should test and add liquid chlorine as often as you can. Every hour is best particularly early in the SLAM process. When Chlorine Loss slows down, you can go to every 2-3 hours. Life certainly can get in the way. The more often you can test and replace, the faster it will go. Every time you test, add enough liquid chlorine to get back to SLAM level for your CYA.
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- Nov 12, 2017
- 12,679
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Yes, SLAM level until the end. It'll be a challenge, as the minute you get to SLAM level, the chlorine starts getting used up! And you can't really fudge by going over SLAM level, because that'll just be wasting chlorine and possibly compromising pool equipment. So the closer to SLAM level you can keep your pool, 24/7, the sooner it'll get cleared. If your schedule only allows you to test and dose a few times a day, it'll take longer than if you were somehow able to test and dose every hour (which, or course, is not realistic if you're not married to a vampire)!
As @PoolStored points out, it's most important to be as diligent as possible at first. As the SLAM begins to take effect, you'll notice the FC holding better, and then you can maybe ease up if you have to. But, again, the better you maintain, the sooner it'll be over.
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So I have been SLAMing since last Tuesday, it has slowed down. Overnight loss last night was 3ppm. I have been maintaining SLAM levels about every 2 hours with the exception of overnight. During this entire process, my pool has been crystal clear and my DE filter pressure as only gone up a little bit. Is it normal that it’s taking this long?? Also, at what point do we worry about PH and Alkalinity? I’m so worried about ruining anything, especially my new heater!
- Jun 22, 2014
- 52,078
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Six days is a fairly common timeline for a SLAM Process. Some do go longer. It sounds as though are are trying to maintain the proper FC (SLAM) level which is good. However an overnight loss of 3 ppm is quite a bit, so there could be a location somewhere algae hasn't been found. Stick with it a bit longer. Six days is not a problem for the pH. I would not lower the FC to check the pH just yet. The TA can wait much longer.
- Nov 12, 2017
- 12,679
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
You're doing great. Follow Pat's advice. What he's referring to is algae hiding in places that aren't getting great circulation, so aren't getting fully exposed to the elevated FC, like inside a ladder, or skimmer, behind the light(s) inside the niche(s), etc. Think like algae, where would you be hiding from the big bad chlorine lady!? You might have to disassemble things to scrub hidden areas and blast them with chlorine.
Clear water is only one criteria, don't get fooled by that. You must pass all three "slam-is-over" criteria before you stop the SLAM, or else you could get stung and have to start all over again.
Keep up the good work!
What if I’ve calculated the wrong CYA? I’m not super confident when testing that. When I tested it myself I was thinking I was seeing the dot but was I?!? What if I’m wrong? Were these last days a complete waste of time and money or am I still killing algae?
- Nov 12, 2017
- 12,679
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
If you're not passing the OCLT, then you're not wasting chlorine. The CYA test sucks, and just about everybody hates it. And nobody knows exactly what their CYA is because of it. Don't stress that, it's not just you. It has a margin of error and there's nothing to be done about that. If the water is clear (or clearing) and your FC is holding a little better each time you test it, and your OCLT continues to improve, then the SLAM is working. It is probably true that if you knew exactly how much water is in your pool, and exactly what your CYA is, and your FC tests were 100% accurate, then you could maybe adjust the SLAM to save a few bucks on chlorine. But all those numbers have a fudge factor, a margin of error, and you're a human, not a robot, so in reality pool maintenance, including a SLAM, is best guess. You're not going to waste 100s of dollars if your CYA test result is a little off. Hang in there. Trust yourself and your test results. Whatever you're doing, it's better than any pool store or pool guy could do, that's a virtual certainty.
Thank you
I will keep going and hope this is done soon!!!
- Nov 12, 2017
- 12,679
- Pool Size
- 12300
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Perhaps this will help with your CYA testing. The images are from the manufacturer's website, from their CYA testing instructions.
You are killing algae anytime you are above minimum FC. *if* you missed the CYA test a little, you lost a little efficiency in the process, but you still did 85% (?) great. No worries at all.
You got this. (And you have some HEAVY hitters helping you
)
Ok-day 8 and no end in sight. I am checking and dosing every 1.5-2hrs. What if I raised my SLAM level from 24 to 27
We'd love to see pictures of the pool in the current state. One thing recommended during a slam is to take a picture from the same vantage point daily to compare your progress.
It's not going to perform any miracles. Slam was optimized for sanitizing VS chlorine burn off. In the mid to high 20s it usually burns off quick and isn't around long.
What / when was the last OCLT results ?
My pool has been clear since day 1. I haven’t seen any signs of cloudiness or algae at all. So I have a BIG jug of the titration agent and am now testing my levels twice to verify and have gotten different results-maybe a drip I didn’t notice or something?? My daughter has been helping so maybe she isn’t taking her time? We are full sun for the grand majority of the day.
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I lost 2ppm overnight last night. I checked it at about 10:00pm and then at 5:45am