For everybody else’s reference, the Walmart bleach was of the lower concentration (3.78qt @ 6% for 2.76 (?) each).
All kinds of issues!
- Thread starter NorthPilot06
- Start date
We’ll consider me confused. Here are the current measurements - recall that I added one bag of shock this a.m.
[FONT="][FONT="]NaCl - 1,800 ppm (lots of backwashing)[/FONT][/FONT]
[FONT="][FONT="]FC - 4.4 ppm[/FONT][/FONT]
[FONT="][FONT="]CC - 0.2ppm[/FONT][/FONT]
[FONT="][FONT="]CYA - 45 ppm[/FONT][/FONT]
[FONT="][FONT="]pH - 7.2-7.3[/FONT][/FONT]
[FONT="][FONT="]TA - 40ppm[/FONT][/FONT]
[FONT="][FONT="]CH - 70ppm
FC was almost non-existent last night, so it seemed reasonable that I would have to SLAM the pool. But CC is negligible today - I can’t put two and two together.
In any event, I’m going to add Chlorine now to bring to Shock levels - I know my CYA is lower than recommended for a SWG, but I’m going to add Chlorine based upon the 45 ppm reading (so a target FC of 18). That means, with a pool size of 12,500, I’ll add 353 oz of chlorine.
Doing that now, but let me know if there are any other considerations that I’ve missed - thanks![/FONT][/FONT]
[FONT="][FONT="]NaCl - 1,800 ppm (lots of backwashing)[/FONT][/FONT]
[FONT="][FONT="]FC - 4.4 ppm[/FONT][/FONT]
[FONT="][FONT="]CC - 0.2ppm[/FONT][/FONT]
[FONT="][FONT="]CYA - 45 ppm[/FONT][/FONT]
[FONT="][FONT="]pH - 7.2-7.3[/FONT][/FONT]
[FONT="][FONT="]TA - 40ppm[/FONT][/FONT]
[FONT="][FONT="]CH - 70ppm
FC was almost non-existent last night, so it seemed reasonable that I would have to SLAM the pool. But CC is negligible today - I can’t put two and two together.
In any event, I’m going to add Chlorine now to bring to Shock levels - I know my CYA is lower than recommended for a SWG, but I’m going to add Chlorine based upon the 45 ppm reading (so a target FC of 18). That means, with a pool size of 12,500, I’ll add 353 oz of chlorine.
Doing that now, but let me know if there are any other considerations that I’ve missed - thanks![/FONT][/FONT]
- Jun 22, 2014
- 52,172
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
You're getting it now!
Now just for easy references, we typically round-up or down (like taxes) on the CYA reading so that we can use the Chlorine/CYA Chart easily. So if your CYA seemed to be 45, just call it 50 which would make your SLAM FC level "20". Bleach is your weapon of choice right now until the SLAM is complete. Once you pass all 3 SLAM criteria, then we'll worry about salt, a higher CYA, and adjusting the SWG output. For now, it's all about maintaining an FC of "20" with regular bleach. Don't forget to check all the other SLAM items noted on the SLAM page (link below) to help it go efficiently. Maintaining the FC level and patience is key.Don't worry about testing anything else right now other than FC. Even the CC can wait a bit until you think you're at the end of the SLAM. If the filter pressure increases by about 20-25%, do a backwash. Brush the pool well and inspect any areas that may hide algae.
Lastly, not sure if I mentioned it before, but for your FC testing you can save some reagents by using a 10ML water sample with one scoop of power. Mix with drops until clear and divide than number in half. Example: 24 drops = FC of 12.
About an hour in, FC still at 20 ppm. Guess it won’t require too regular of adjustments (after all, my pool wasn’t green) 
- Jun 22, 2014
- 52,172
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
That's great! Perhaps do an overnight test just to see if you lose more than 1 ppm from bedtime to morning (before the sun hits the water) to see how well your water really holds chlorine. You might get away with a fairly quick SLAM. Good luck!
- Jun 22, 2017
- 861
- Pool Size
- 35000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45
If you need to buy more chlorine, Walmart sells "Liquid Shock" that is 10% chlorine. That one tends to be a bit cheaper per oz of chlorine than the 6% and 8.25% bottles, plus you don't need to buy as much cuz of the increased percent.
Thanks all - I measured my FC this morning and it was 18.5 ppm, so a 1.5 ppm drip overnight. I guess I will keep the levels high for one more day then.
- Jun 22, 2014
- 52,172
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Yes, hang in there. This is the toughest part when you are so close. Take advantage of this time to really inspect all areas of the pool where water sits, brush the surfaces really well, and clean the filter if needed. Good luck tomorrow.
A surprising amount of chlorine loss happened during the day today, not sure if that was the byproduct of a beautiful, 80 degree and sunny day with low CYA or not. But I ended up putting another 2.5 bottles of bleach in the pool, in two phases. Based upon my last measurement, I’m back up to 20.5 ppm.
Was my daytime drop expected (with such a small drop overnight last night of 1.5 ppm)? Just wondering what your experience has been.
Thanks,
Michael
Was my daytime drop expected (with such a small drop overnight last night of 1.5 ppm)? Just wondering what your experience has been.
Thanks,
Michael
- Jun 22, 2014
- 52,172
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
It will be interesting to see what your overnight FC loss was. Your last CYA was between 40-50, so we rounded-up to 50. A CYA of 50 should be fine this time of year to preserve FC from the sun alone. You will lose a bit more FC during a SLAM because your FC is at the higher range on the Chlorine/CYA Chart, so the FC can drop a bit more from that SLAM goal of 20. The results of your OCLT will tell us if there are organics present in the water contributing to additional FC loss. If you passed the OCLT, then you can let the FC fall naturally to the recommended range of 6-8 for your current CYA. Good luck!
3 ppm loss overnight (20.5-17.5). More than on the first night surprisingly.
Added back in Chlorine (ended up at 21.5 ppm - tried to stir it around but maybe it’s not evenly distributed. Or the concentration on this brand is higher (not listed but expected to be 6-9%). Oh well, I don’t think 21.5 ppm will hurt things and I won’t be home to put in more until 6:30 this evening.
Added back in Chlorine (ended up at 21.5 ppm - tried to stir it around but maybe it’s not evenly distributed. Or the concentration on this brand is higher (not listed but expected to be 6-9%). Oh well, I don’t think 21.5 ppm will hurt things and I won’t be home to put in more until 6:30 this evening.
Well, I’m stuck. I’m out of R-0871. And bleach lol. I’ve dumped in about 7.5 gallons of bleach to date and I haven’t seen a lot of dead algae precipitate out - but it does look like my vinyl liner is getting bleached out a bit, color-wise.
Not sure what to make of it all, but that’s my current status. Pat, any ideas? Thanks for trying to help.
Not sure what to make of it all, but that’s my current status. Pat, any ideas? Thanks for trying to help.
Have you been adding the bleach slowly in front of the deep end return? Where in the DFW Metroplex are you? I have some extra R-0871 I can give you if you are close.
How are you adding the bleach to the pool? Which parts of the liner appear bleached? bleaching out a liner with liquid bleach that gets decent circulation and mixing is difficult. FC of 21ppm with a CYA of 45-50ppm is not really that harsh at all. Less harsh than your local public pool with zero CYA. Chart . Are you sure you aren't seeing white "stuff" precipitate out? Try sticking your brush down and see if the water is cloudy or you can stir up anything.