Guidance in SLAM process

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C

chris-md

0
Jul 28, 2017
37
Silver Spring, MD
Hello everyone!

My name is Chris, living in the greater D.C. area. I first want to thank this forum for the valuable information. I've lurked a bit trying to solve my algae problem; this forum and the pool school has been invaluable.

I have an approximately 40,000 gallon standard pool. Sand filter with inground spa.

I developed the dreaded SWAMP maybe 2 weeks ago (became an oddly pretty neon green color). Found here and maybe the last 5 days started the SLAM process by doing the following:

1) absent a more sophisticated chemistry test kit I had to start simply by dumping cumulatively 8lbs or so of cal-hypo (I knew early on that I had almost no calcium so was good to use that for the time being).

2) twice daily brushing of the pool sides

3) twice daily backwash/rinse

4) running the Polaris to agitate algae into the water column.



My Taylor 2006c kit came today and I'm finding th following results

TC: 28 ppm (FC=27ppm, CC=1ppm)
pH= 7.4 (meaningless at this level of chlorine, no?)
CYA= 50-60 (not really sure what constitutes the black dot disappearing)
TA=90ppm
Harness= 200ppm (need to ease off cal hypo at this point)

Where I'm hoping for help:
1) where do I go from here? It's been at 28ppn+ for three days and am not seeing any color change: light green and hopelessly cloudy. If it weren't for the cloudiness I would be able to see the deep end of the pool. Cloudiness has actually gotten worse the last couple days.

2) I smell chlorine! I generally understand smelling chlorine is not good, but I'm not sure if it's natural to smell it during the SLAM process. But it smells like a public pool = chloramines? The 1ppm combined chlorine, based only my research, is not a good thing.

Thank you in advance for my help you can provide.??
 
Welcome to TFP! Glad you found us! Glad you joined!
I'll give you some answers:
chris-md said:
I have an approximately 40,000 gallon standard pool. Sand filter with inground spa.
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do they share the same water/spillover? or completely separate?
chris-md said:
by dumping cumulatively 8lbs or so of cal-hypo
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Cal-hypo can sometimes cloud the water, but it sounds like your clouding is algae...probably mostly anyways
chris-md said:
pH= 7.4 (meaningless at this level of chlorine, no?)
CYA= 50-60 (not really sure what constitutes the black dot disappearing)
Harness= 200ppm (need to ease off cal hypo at this point)
Click to expand...
1. Correct, PH test is invalid if FC over 10.
2. Black dot picture here, linked from this page
3. CH - vinyl or plaster pool?
chris-md said:
Where I'm hoping for help:
1) where do I go from here? It's been at 28ppn+ for three days and am not seeing any color change: light green and hopelessly cloudy. If it weren't for the cloudiness I would be able to see the deep end of the pool. Cloudiness has actually gotten worse the last couple days.
Click to expand...
SLAM Process procedure is the easy answer. You really have to do it all, no shortcuts. My real advice, based on dozens of threads helped in, is to test the FC and bring it back up to shock for your CYA ([FC/CYA][/FC/CYA]) as often as you can for the next couple days, as often as every 30 mins, until it holds, then every 2 hours until it holds, then 4 hrs etc. The faster you kill the algae, the sooner you'll have your pool back and can filter out the dead algae. The shock FC does the much, much faster than lower than the shock FC. Brush the bottom if you can, i see you're doing the walls already.
chris-md said:
2) I smell chlorine! I generally understand smelling chlorine is not good, but I'm not sure if it's natural to smell it during the SLAM process. But it smells like a public pool = chloramines? The 1ppm combined chlorine, based only my research, is not a good thing.
Click to expand...
You smell CC yes. That tells you your FC is working hard and needs to be replenished/topped off. The sun will burn off these CC for you, so smell will be most intense after bleach additions when FC is at shock and max effective sanitizing (most CC generated) and when the sun is not on the pool. It will be gone by the end of the SLAM and you have a scentless pool.

Also, please add those pool stats and test kit to your signature via these instructions.

Next round of questions! Anything I missed?
 
Thank you so much for the reply! The spa and pool are part of the same system. Not separate.

I think you basically affirmed I'm on the right track, perhaps a bit of patience needed on my part - we've been above shock levels for maybe 4-5 days. I mentioned the walls but the floors are being hit as well.

The only follow up question I have is pertaining to your last statement about topping off the chlorine. I'm already above shock value (I'm at 28, shock is 20-24ppm). I need to add more at this point? I'm trying to understand this intersection of being over shock value but still needing more based on CC value. If I add more, what does that do the the current CC? I feel like that's an important point I need to understand, the high CC value as an indicator of sorts in chlorine performance.
 
Good questions! So you add bleach/cal-hypo and that adds FC. FC drops due to being "used up" oxidizing organics (plant matter/algae/bacteria/insects/etc) and a percent is lost to sunlight degradation "unavoidable sun god sacrifice."

Each day a healthy TFP pool will see FC drop 1-4ppm if CYA is appropriate for their location and FC level. A SWAMP generally loses more, sometimes lots more...like 20+ a day isn't impossible.

One thing we need to confirm - when it first went green - was it crystal clear green or murky/cloudy green?

In a SLAM, we accept that we're going to lose some extra FC to the sun - but we're okay with that because we want a crystal clear pool to swim in as soon as possible.

As the FC (active sanitizer) is used up cleaning your pool, it is converted to CC (not effective sanitizer) until they are broken down further by the sun really fast. They smell when they're in CC stage, before the sun burns them off. If you have a strong CC smell, a lot of your bleach did its job and is now retired awaiting death, and if you check your FC level, you should find it dropped, and you can use PoolMath to calculate how much bleach would be needed to bring you back up to shock FC.

If you tested your FC 5 days ago and it was 24-28, each day it should fall at least 1ppm and probably more like 4+. By now you should be down below 24 no matter what. The only reasons it would be higher than 24 now are:
1) you have a SWCG (salt water chlorine generator)
2) You added more or stronger bleach than you thought
3) You have trichlor pucks floating in the pool or added some source of FC
4) You have an inline chlorine feeder
5) someone added something without you knowing
6) manual testing error/bad test chemicals
7) you are the recipient of some sort of holy/supernatural blessing
8) you have a magic pool that I wish to study

Usually, it is testing error or adding a source of FC you didn't know raises FC/floaters/swg. I still have yet to find a magic pool...sadly. Maybe you're it!

Thanks for understanding my playful attitude.

So - to recap - add bleach/solid chlorine product and FC goes up. It breaks down and gets used up, falling at least 1 a day, usually more, and smells until the sun burns of the CC. You need to bring FC back up to shock frequently, multiples times a day, to really clear a swamp fast.

To make sure you're testing FC and CC right, here are the videos, extended directions, and TF-100 test kit directions (similar, but not identical, potentially worded better/more detail, but still follow size and drops in your directions, and OKAY to use 10mL sample size test instructions to save chems).

So, please touch up your FAS-DPD and CYA testing and post results, we'll go from there. (CYA must be sunlight outdoors as explained on extended directions)
 
Ok that makes sense, and something I intuited. Reasons for chloramine/ammonia production I read about only reference swimmers (body oils, fecal matter, urine, you name it) as the reason. I thought maybe that was a subset of the larger organic matter picture but wasn't ready to draw that conclusion on my own. So chloramine really is the oxidative byproduct of chlorine interacting with ANY oorganic matter. We do live in the woods but are always on top of cleaning out leaves.

The pool changed...maybe two weeks ago this weekend. When the change first registered - a day or two after it started - I will ill say this curiously coincided to the first time I drained the spa - through the filter - into the pool. The spa wasn't great looking (suspended dirt particles, small leaves, etc) so I drained it through the filter to give it a nice cleansing.

I will ill revisit the chlorine readings tomorrow. Though we are having strong run events so this will really throw things off
 
This is how they are always set as standard, yes. This has resulted in the spa looking pretty rough( hence the draining. Lately however I have been running t tksuch that the spa win drain is actually opened a tiny bit so some of the spa can drain out. The standard spillway mode I think created slightly stagnant water.
 

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