Dark swampy green pool TF-100 reagent test

[PoolStored]

1. Should I take the pH reading before adding LC?

Sure. Won't matter...

2. How well does CYA store in 80-90F day weather?

CYA is generally stable in storage, independent of heat.

3. I estimate I will need 8lb of CYA to raise my CYA from 0 to 45 (and 5lb of CYA to raise my CYA from 0 to 30) - should I purchase 2 bags of 4lb CYA @$15/bag or 1 bag of 20 lb CYA @$58/bag?

https://www.amazon.com/dp/B011AFBUJS
I ask because I'm unsure how much more CYA I will need beyond the initial 8lb, and whether the additional 12lb is going to be useful

That is just fine CYA. You might lose 5-10ppm per month in the summer, less so in shoulder and winter months. Since CYA is consumable and stable for storage, I buy a bit ahead of what I need and find the best price.

 

[ajw22]

1. Should I take the pH reading before adding LC?

Yes. Wasn't that discussed above?

2. How well does CYA store in 80-90F day weather?

CYA is very stable and can be stored for years.

3. I estimate I will need 8lb of CYA to raise my CYA from 0 to 45 (and 5lb of CYA to raise my CYA from 0 to 30) - should I purchase 2 bags of 4lb CYA @$15/bag or 1 bag of 20 lb CYA @$58/bag?

Amazon.com

I ask because I'm unsure how much more CYA I will need beyond the initial 8lb, and whether the additional 12lb is going to be useful

She will use the CYA eventually if she properly maintains her water chemistry.

 

[plnewb]

aunt also has a unconnected/isolated spa/hot tub, so I guess I would need CYA for that too (knowing my uncle never used CYA)?

So I am ordering the 20lb from Amazon. If I should sneak in something else in that Amazon order, please let me know!

 

[ajw22]

aunt also has a unconnected/isolated spa/hot tub, so I guess I would need CYA for that too (knowing my uncle never used CYA)?

Depends how the hot tub is sanitized.

 

[Brian PacNW]

aunt also has a unconnected/isolated spa/hot tub, so I guess I would need CYA for that too (knowing my uncle never used CYA)?

This article may help:

Spa & Hot Tub Maintenance A Basic Guide

Hot Tub Maintenance can be done easy with a few tricks. Hot tub chemicals, rashes, and schedules are all covered in this easy to grasp article.

www.troublefreepool.com

And this wiki page seems to be more about setting things up, but also helpful:

Hot Tub Basics - Further Reading

www.troublefreepool.com

 

[plnewb]

I read the Spa links and none of them mention a practice of completely draining (and optionally filling) the HT every 3-4 months: that's what I do for my own inground, isolated HT, but that is because my pool guy who I respect a lot, does it for me.

Is that hocus pocus? He's never sold me snake oil before.

 

[mknauss]

Did you read the article linked above? Quarterly maintenance includes drain and refill.

 

[plnewb]

I had a closer look at Spa & Hot Tub Maintenance A Basic Guide and initially misunderstood "drain and refill" to mean just to partially drain and refill at and above the skimmer line.

It looks like a complete (as in empty the spa) drain and refill was implied

 

[plnewb]

It's a good practise that one shouldn't be adding LC in the morning when the sun's out full blast and will blow out all the LC in a matter of hours (for a pool that has currently 0 CYA)

But, if I am going to add LC to a pool in the evening when there's no direct sunlight, is it OK to start dosing a pool with CYA (that has currently 0 CYA) in the morning, so there's some CYA already in the pool when the LC will be added?

Or is adding CYA in a pool (that has currently 0 CYA) better added at the same time the LC is being added

This is the CYA I'm using:

Amazon.com

 

[mknauss]

Add the chemicals when you can. No real advantage.

 

[plnewb]

Add the chemicals when you can. No real advantage.

Thank You, but I will humbly request this thread to be closed now as there are these 12 different questions that are just very basic questions of me trying to understand pool chemistry ranging from CYA to CC/FC/TC etc and nothing to do with actually fixing a pool now all merged into this thread.

For example: An unrelated post to do with a hot tub that's not even connected to this pool is also merged into this thread.

If I were to read this thread, I would be extremely confused what's going on.

In essence this post has now become a massive dump of all the questions I have ever asked on this forum

I personally would have a hard time keep track of things if I were to revisit this thread myself in a few months

Can I close this thread and start a focused one with just one post with details about the pool and then others can join in with their posts that are on the topic of troubleshooting that specific pool, please?

 

[JJ_Tex]

Thank You, but I will humbly request this thread to be closed now as there are these 12 different questions that are just very basic questions of me trying to understand pool chemistry ranging from CYA to CC/FC/TC etc and nothing to do with actually fixing a pool now all merged into this thread.

I'll play devil's advocate. I was typing a response to your thread about adding CYA, but had no idea that you were also going through a SLAM and had algae.

By the way, here is my response on the Adding CYA question which was moved before I hit the Post Reply button.:

CYA takes hours/days to fully dissolve so add it whenever you can. The typical method recommended here is to fill a sock with it and hang it off of a pole in front of a return jet. It seems a bit goofy, but that stuff is acidic and can mess with your pool finish and filter grids so this allows it to dissolve in the water without touching anything undissolved.

I also see your signature describes your pool as a "green swamp". Are you trying to SLAM? You need ~30 ppm to do a proper SLAM, and be careful not to overshoot that number or you will need even more chlorine to clear it up.

 

[plnewb]

your thread about adding CYA, but had no idea that you were also going through a SLAM and had algae

That's ok! As that thread progressed we could have discussed different scenarios that would change the answer - that's the beauty of having hyperfocused posts about a topic - you can really go deep

For sure, I am not the only one who's going through a SLAM because I have an algae problem and wondering about this - there will be more people in the future and they for sure won't be interested in my specific situation.

Imagine someone typing into Google "Does it matter when I start dosing a pool with CYA" and coming across a forum post titled "Dark swampy green pool TF-100 reagent test" - would you click that link or would you prefer a post titled "Adding CYA to a pool without any CYA" that we can later rename to "Does it matter when we add CYA to a pool without any CYA"?

All that said, I do understand that at this forum we are more focused on specific pool situations, but that also means there are jewels and nuggets of high quality information hidden in posts that are titled "Shoot what do I do next!!!!"

Are you trying to SLAM?

Yes, I begin today

You need ~30 ppm to do a proper SLAM, and be careful not to overshoot that number or you will need even more chlorine to clear it up.

Copy - I knew that already from reading the blog post - but it didn't mention whether the time of application mattered (like it does for LC) and that's what my focused thread was about

 

[plnewb]

For anyone following, the TF-100 test have exposed 0.5 levels of FC, CC and 0 CYA.

This morning I bought a 50lb bag of CYA

After lunch I will be headed to the pool and here's my amateurish plan:

1. Put a pool sock of CYA in the skimmer (is that a bad idea? stop me now!) and a pool sock of CYA hanging off the brush rod by the return jet (second bad idea? stop me now, please!)
2. Wait 4 hours until it becomes cooler outside (it's 95F right now)
3. Take a pH and CYA measurement
4. Add HCl, if needed, to reduce the pH to 7.4, or Baking soda, to increase the pH to 7.4
5. Then add LC as needed to begin SLAM (will calculate during #2)

 

[mknauss]

Fine to add CYA that way. Squeeze the socks every so often.
No need to test CYA. Assume what you put in is what is in the water. Test in a couple days.
Lower the pH to 7.2 at the same time.
Add chlorine to SLAM level. No need to wait. The sooner you start, the sooner it is done.

 

[JJ_Tex]

How much CYA are you going to add? A 50lb bag should last you a lifetime. By my math 5lbs of stabilizer should add 30 CYA to your pool which is perfect for a SLAM.
Unless you are 100% sure of your 0 CYA (like a new fill or something) I would start off with 3 lbs and retest a few days later.

 

[ajw22]

Solid stabilizer need 48 hours or more to dissolve and circulate. Don’t wait until you get a CYA 30 reading. Assume the CYA is in the water when you start adding it and move on to add LC.

You can test and add CYA during the SLAM if necessary.

 

[plnewb]

Unless you are 100% sure of your 0 CYA (like a new fill or something) I would start off with 3 lbs and retest a few days later.

4lb (recommendation was 88oz but I'm playing it safe as I can always add more later as JJ_Tex mentions) 100% CYA now dissolved into the 21k gal pool

Proceeding to do pH test and then will take corrective actions to place pH between 7.2-7.6 before adding LC.

1. It's my understanding that we should do the FC, CC test before we do the pH test, as a FC >= 10 (which is what happens during SLAM) makes the pH test useless. This essentially means we get to do the pH test only before the start of SLAM and NEVER during SLAM?
2. The reason why the pH test is necessary is because the LC added will be more effective when we start from a pH of 7.2-7.6.
3. For my specific case of FC = 0.5 this is irrelevant and I can test pH as much as I want before the start of SLAM but this is something worth keeping in mind in the future
4. Since I added the CYA, I will expect the TA and pH to have changed from the readings before addnig CYA
5. Since SLAM begins today, I have to add 2.6G LC to add to the pool to hit FC = 12. I am lazy so I will add 3G and that should land me at FC = 13
6. I will do a FC, CC test tonight before leaving and early tomorrow morning before the sun starts to hit the pool and this could be a good OCLT too? (maybe I am being too hasty as the algae will eat up the Cl overnight anyways)

Solid stabilizer need 48 hours or more to dissolve and circulate. Don’t wait until you get a CYA 30 reading. Assume the CYA is in the water when you start adding it and move on to add LC.

OK, will take a CYA reading Wednesday

 

[proavia]

For a SLAM, test pH and lower to 7.2 before starting the SLAM - (not 7.2 to 7.6).
No need to test pH until the SLAM is complete and the FC is 10 or lower.

No real need to do the CC test - at least for a few days. Focus on the FC for now.

 

[plnewb]

As I go through SLAM I had some questions:

1. I am targeting CYA 30.
It's my understanding that in general pools chlorinated with tablets or liquid chlorine should have CYA up to 40ppm, so 30 is a great starting point as CYA can only grow over time?

2. Then, following the 7.5% rule, the FC should be 2.25ppm?
3. But this is the level I should maintain when the pool is healthy but since that's not the case right now, I will maintain it at 12ppm to purge the contamination/algae?

4. This pool isnt in my home - pretty far away from it so I can only visit it early in the morning, before work and maybe twice at night after work.

So I can add the LC once early in the morning or twice at 6-7PM and 9-10PM every evening

Although I have CYA 30, isn't it still better to add LC in the evening, so I add LC twice every evening ~3 hours apart and never early in the morning when the sun will beat on the FC anyways?