Pool not holding chlorine

Until you are able to lower the CYA, it won't hurt to leave it on because your FC level needs to be much higher than normal according to the FC/CYA Levels. Hopefully you can avoid an algae outbreak, so keep the FC elevated. Once you exchange water you can maintain a normal FC level and we'll evaluate more from there.
I am going to start my water exchange today, but I am confused as to the best way to do this. I have a DE system with a drain to waste setting. Should I run that, while simultaneously running my hose into the pool? (Drain from main drain in deep end and put hose in shallow end)? Do I do a little at a time, or do I do it all at once? Should I drain water to a certain level then refill with hose? I’m just not sure the best method and I’ve read conflicting directions. What do you recommend?
 
You really need to fill in your signature. Advice about how best to exchange the water in your pool is very much dependent on what type of pool you have. And it's asking a lot of the helpers here to expect them to read or reread your entire thread, on the off chance you might have mentioned what type of pool you have in one of your posts.

The fastest, cheapest way to exchange water is to drain the correct amount, then refill it. But depending on your type of pool, the surrounding earth and how much you plan to drain, you can damage or completely destroy your pool by using that method. Or it could go swimmingly and be just fine.

So let's start with your siggie, and go from there. Use mine as an example.
 
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You really need to fill in your signature. Advice about how best to exchange the water in your pool is very much dependent on what type of pool you have. And it's asking a lot of the helpers here to expect them to read or reread your entire thread, on the off chance you might have mentioned what type of pool you have in one of your posts.

The fastest, cheapest way to exchange water is to drain the correct amount, then refill it. But depending on your type of pool, the surrounding earth and how much you plan to drain, you can damage or completely destroy your pool by using that method. Or it could go swimmingly and be just fine.

So let's start with your siggie, and go from there. Use mine as an example.
I’m sorry-I thought I had completed it. I’ve gone into my profile multiple times and added everything I know and added notes in the “about me” section. I see my notes aren’t up there and the filter info is missing too. What am I doing wrong? Do you mean that I need to add it at the end of each of my posts? I’m sorry-I’m confused
 
There is a specific field that you fill in, within Settings, that will appear at the end of each of your posts (what we call your signature). You don't add that each time to each post. If you click the link I gave you, you should see the signature field to fill in. This one:
https://www.troublefreepool.com/account/signature
 
So I drained as much as I could-just below the skimmers, I lost prime trying to go further-and added water. This definitely did not lower my CYA enough. Here are my numbers:
FC- 0 couldn’t put enough DPD powder to turn it pink at all so I gave up and am assuming there isn’t any CC either
PH-7.4
TA-200
CH-275
CYA-100- I did the extended test to try to get as accurate as possible
So- next steps? Is it algae I can’t see?? My pool is still very clear. Should I run the hose in the shallow end while draining through the main drain? I am spending a lot on liquid chlorine. I did shut of my chlorinator because I didn’t want to add to my CYA. Is that a mistake?
 
You are correct to stopping the inline chlorinator. You definitely do not need anymore CYA. No FC is never a good thing. Something is eating the chlorine, and the best way to confirm, if you haven't done so already, is to do an Overnight Chlorine Loss Test. With no sun on the water at night, add enough liquid chlorine to get the FC up to about 5-6 ppm. Just leave the pump running (low speed is fine) and compare the FC the next morning before the sun rises. If you lose more than 1 ppm of FC during this overnight test, you have algae.

You can do the Overnight Chlorine Loss Test even with a high CYA because the sun UV is not in the equation. If you fail the OCLT and need to do a SLAM Process, you can then consider exchanging a bit more water, but at least you'll know why the FC is falling.
 
You are correct to stopping the inline chlorinator. You definitely do not need anymore CYA. No FC is never a good thing. Something is eating the chlorine, and the best way to confirm, if you haven't done so already, is to do an Overnight Chlorine Loss Test. With no sun on the water at night, add enough liquid chlorine to get the FC up to about 5-6 ppm. Just leave the pump running (low speed is fine) and compare the FC the next morning before the sun rises. If you lose more than 1 ppm of FC during this overnight test, you have algae.

You can do the Overnight Chlorine Loss Test even with a high CYA because the sun UV is not in the equation. If you fail the OCLT and need to do a SLAM Process, you can then consider exchanging a bit more water, but at least you'll know why the FC is falling.
Ok-I need to SLAM because I know I lost more than 1ppm overnight. However, I can’t SLAM at that high of a CYA can I? Should I try exchanging water first? I am dreading my water bill this month….
 
Ok-I need to SLAM because I know I lost more than 1ppm overnight. However, I can’t SLAM at that high of a CYA can I? Should I try exchanging water first? I am dreading my water bill this month….
Yes, you should exchange first. Some help:

 
So I drained as much as I could-just below the skimmers, I lost prime trying to go further-and added water. This definitely did not lower my CYA enough. Here are my numbers:
FC- 0 couldn’t put enough DPD powder to turn it pink at all so I gave up and am assuming there isn’t any CC either
PH-7.4
TA-200
CH-275
CYA-100- I did the extended test to try to get as accurate as possible
So- next steps? Is it algae I can’t see?? My pool is still very clear. Should I run the hose in the shallow end while draining through the main drain? I am spending a lot on liquid chlorine. I did shut of my chlorinator because I didn’t want to add to my CYA. Is that a mistake?
OK, good job on the signature! Thank you.

You have to have the pump off to drain water, unless your plumbing is such that you can pump through the main drain only while the skimmers are closed off. If you can't do that, then you need to remove water in some other way. You can do that by siphoning, if you happen to have the hilly terrain that would require, or you use a stand-alone submersible pump, a small one which you can purchase or rent. Something like this:


There are tons of brands and styles, such that I'd be hard pressed to recommend a specific one. I want one myself, but haven't yet been able to pick the right one. Or you can usually rent one for a day, like from HD or Lowes. You can spend as little as 50 bucks, or go deluxe and spend hundreds.

You have a vinyl pool, which I don't have any experience with. But I know that you have to be careful about how much water you remove at once. The water is part of the structure of a pool (any pool) and if you remove it, you run the risk of compromising that structure. Like caving in the sides or floating the bottom. I have a concrete pool, but I still wouldn't drain more than a few inches. I would do a no-drain exchange, which you might have already read about. It's the slowest, and the most expensive way to exchange water, but it offers virtually zero risk to your pool if you do it right.

So,

1. work out if you want to do a quick exchange, or a no-drain exchange. (Read the link @PoolStored gave you.)

2. figure out your plumbing to determine if you can use your filter pump, or if you can siphon, or if you need a submersible pump.

3. then figure out how much water you need to exchange. You'd use Pool Math to do that.

Holler if you need help working out any of those three things, and then we'll have the makings of a plan. You're not going to get your CYA right by just stabbing at the problem. You need a plan, possibly some equipment, and then you'll be good to go.

In the meantime, keep your FC up as best you can, so that your pool doesn't go totally green. Because that will just make the fix all the more difficult and expensive.

For what it's worth, you're in this fix because of the tabs. They are the devil. They're super convenient, but you were probably never told that is an unsustainable method of sanitization. Eventually they add too much CYA, and then you must exchange water to start over. You didn't do anything wrong, per se, but there are much better ways to keep your pool sanitized. And we'll show you how once we get that CYA down.

If you want to follow the path I was on, after my tab feeder ruined my pool, I stopped using it and then never used it again, finally ripping it out of my plumbing. I haven't had any algae, and I haven't had to exchange any water, for almost five years now. But first things first. Work on that list and check back in with any questions.
 
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OK, good job on the signature! Thank you.

You have to have the pump off to drain water, unless your plumbing is such that you can pump through the main drain only while the skimmers are closed off. If you can't do that, then you need to remove water in some other way. You can do that by siphoning, if you happen to have the hilly terrain that would require, or you use a stand-alone submersible pump, a small one which you can purchase or rent. Something like this:


There are tons of brands and styles, such that I'd be hard pressed to recommend a specific one. I want one myself, but haven't yet been able to pick the right one. Or you can usually rent one for a day, like from HD or Lowes. You can spend as little as 50 bucks, or go deluxe and spend hundreds.

You have a vinyl pool, which I don't have any experience with. But I know that you have to be careful about how much water you remove at once. The water is part of the structure of a pool (any pool) and if you remove it, you run the risk of compromising that structure. Like caving in the sides or floating the bottom. I have a concrete pool, but I still wouldn't drain more than a few inches. I would do a no-drain exchange, which you might have already read about. It's the slowest, and the most expensive way to exchange water, but it offers virtually zero risk to your pool if you do it right.

So,

1. work out if you want to do a quick exchange, or a no-drain exchange. (Read the link @PoolStored gave you.)

2. figure out your plumbing to determine if you can use your filter pump, or if you can siphon, or if you need a submersible pump.

3. then figure out how much water you need to exchange. You'd use Pool Math to do that.

Holler if you need help working out any of those three things, and then we'll have the makings of a plan. You're not going to get your CYA right by just stabbing at the problem. You need a plan, possibly some equipment, and then you'll be good to go.

In the meantime, keep your FC up as best you can, so that your pool doesn't go totally green. Because that will just make the fix all the more difficult and expensive.

For what it's worth, you're in this fix because of the tabs. They are the devil. They're super convenient, but you were probably never told that is an unsustainable method of sanitization. Eventually they add too much CYA, and then you must exchange water to start over. You didn't do anything wrong, per se, but there are much better ways to keep your pool sanitized. And we'll show you how once we get that CYA down.

If you want to follow the path I was on, after my tab feeder ruined my pool, I stopped using it and then never used it again, finally ripping it out of my plumbing. I haven't had any algae, and I haven't had to exchange any water, for almost five years now. But first things first. Work on that list and check back in with any questions.
So I did end up buying a small submersible pump and was planning on doing that. Since I had issues getting my water low enough in the fall when it came time to close it. I have to drain it to below the return jets to get those blown out and plugged for the winter (yay Minnesota) so instead of running my pump, I thought I’d do the submersible. Just to clarify, if I’m using a submersible, did u mean I should shut my pump down while draining?
 
So I did end up buying a small submersible pump and was planning on doing that. Since I had issues getting my water low enough in the fall when it came time to close it. I have to drain it to below the return jets to get those blown out and plugged for the winter (yay Minnesota) so instead of running my pump, I thought I’d do the submersible. Just to clarify, if I’m using a submersible, did u mean I should shut my pump down while draining?
Yes. Turn off the circuit breakers to your pad for extra safety, so that nothing can inadvertently turn your main filter pump on.

Did you decide if you're going to do a drain and fill, or a no-drain exchange?
 
Well, I didn’t really calculate it, I eyeballed it which I know is maybe not such a great method per TFP standards :D but I decided to go as shallow as I felt comfortable. Fortunately, I tested my CYA this AM after leaving the filter on all night and I got my CYA to 60. Thank goodness! I know that’s not the ideal, but I will start my SLAM tonight if I can. Just one question, my PH has consistently been around 7.4. I see it says I should get it to 7.2. What do you recommend to get it there?
Thank you all for your help and advice! I’m glad I found this forum.
 
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Well, I didn’t really calculate it, I eyeballed it which I know is maybe not such a great method per TFP standards :D but I decided to go as shallow as I felt comfortable. Fortunately, I tested my CYA this AM after leaving the filter on all night and I got my CYA to 60. Thank goodness! I know that’s not the ideal, but I will start my SLAM tonight if I can. Just one question, my PH has consistently been around 7.4. I see it says I should get it to 7.2. What do you recommend to get it there?
Thank you all for your help and advice! I’m glad I found this forum.
Muriatic acid is best to lower pH. See here for safety precautions:


You won't need to add a lot to drop from 7.4 to 7.2, but it's worth doing as once your FC goes above 10ppm the pH test is invalid (it gets bleached out). So you can't test the pH during the SLAM.
 
Ok-I see pool math tells me it’s about 2 quarts. I will test both alkalinity and ph tonight again before I add the acid…assuming I can find acid anywhere…is the “acidblue” brand true muriatic acid? Or should I be looking for something else?
 
Any muriatic acid is fine. The stuff that's "green" is an odd concentration - instead of 15% or 31% it's like 20%, so you'd have to kind of go between the recommendations for those two concentrations. But it still will work.
 
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Well done on the water exchange. Have you considered installing a saltwater chlorine generator (SWG or SWCG)? The reason I ask:

While there is nothing technically wrong with using tabs, you now know first hand their primary drawback. This was not a one-time fluke, this is what tabs are: convenience for X number of months, then a water exchange. Lather, rinse, repeat. Since you only got down to CYA:60, you'll be doing the next exchange that much sooner.

If you don't want to go through that again, you basically have two choices:

1:
Stop using tabs altogether, and start using only liquid chlorine. , Which is regular testing and then dosing of the correct amount of chlorine, including buying, lugging and storing adequate amounts of liquid chlorine. This is how the vast majority of TFP members care for their pools.

Or 2:
The other alternative is automating your chlorine dispensing, which is basically one of two ways: a chlorine injection system, which is a large tank and a small pump and some sort of timer mechanism that squirts chlorine into your pool at the necessary internals. This also requires buying and lugging liquid chlorine, but you can store it in the chlorine tank. Or, you can install a SWG. They make chlorine on the fly, right in your pool. No more tabs, no more buying chlorine or lugging it or storing it. The chlorine is always fresh. You push a few buttons, and that's it. There is a very large contingent of us here at TFP that swear by their SWGs, and would rather fill in their pools then own one without an SWG! I happen to be one of those. They work great, and the convenience is well worth the expense.

For a time, the long term cost of an SWG was about the same as the long term cost of buying liquid chlorine. With recent economic forces, we'd have to double check on how that comparison is still holding up, because both SWGs and liquid chlorine are more expensive than just a few years ago. But while the up front cost of an SWG is expensive, when you figure in the cost of liquid chlorine or tabs, plus water exchanges, then the cost of an SWG makes much more sense.

And the other "plus," is that SWGs require more CYA in the pool, usually around 70-80, so your current CYA of 60 would actually be a little low, instead of too high.

Something to think about. That was the very simple/short version, there are other things to consider about all the various ways to keep your pool sanitized, which we can walk you through, but this might be the time to consider something other than what you've been doing.

Good luck with the SLAM. You're doing great so far.
 
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