Refilled Pool after Draining - Ready to SLAM But Have Questions

[chris87]

I recently had the coping and tile in my pool replaced. The water was drained, and I just refilled it. Since I'm now starting from scratch, I'm confused about the best way to SLAM. I assume that there is no CYA in the water, but I will test it. I normally use bleach, but I was wondering if I should use dichlor. Is it a bad idea to keep the CYA lower while SLAMing, so that I don't need as high shock FC? I'm just not sure what I should target, and whether I should use the sock CYA method, liquid form, or dichlor. I tested my pH and that looks good.

Does anyone know if there are any issues with SLAMing after having new coping/tile installed?

Thanks in advance for any suggestions.

 

[Richard320]

Dichlor and trichlor are very acidic. So besides adding FC and CYA, they'll lower pH and TA a lot. Test the fill water and then make a decision. You might end up making a lot of extra work for yourself trying to fix them. Plain granular CYA dissolves in a couple days. The expense of the liquid stuff probably isn't worth the gains.

Why SLAM if it's a fresh fill? Was it a real swamp before draining?

 

[chris87]

Dichlor and trichlor are very acidic. So besides adding FC and CYA, they'll lower pH and TA a lot. Test the fill water and then make a decision. You might end up making a lot of extra work for yourself trying to fix them. Plain granular CYA dissolves in a couple days. The expense of the liquid stuff probably isn't worth the gains.

Why SLAM if it's a fresh fill? Was it a real swamp before draining?

Thanks for your post. This will sound really dumb, but I didn't even realize that I don't need to SLAM if it's a fresh fill. I'm so used to doing it every year when I open the pool that I didn't even think about it. What is the best way for me to proceed? Should I start by dissolving CYA and adding some bleach? I assume that I want the CYA steady before turning on the SWG. Thanks again.

 

[Richard320]

Thanks for your post. This will sound really dumb, but I didn't even realize that I don't need to SLAM if it's a fresh fill. I'm so used to doing it every year when I open the pool that I didn't even think about it. What is the best way for me to proceed? Should I start by dissolving CYA and adding some bleach? I assume that I want the CYA steady before turning on the SWG. Thanks again.

I'm assuming you want it swimmable in a hurry, maybe some whiny kids begging to get in.

Test pH, TA, and CH. You know that tap water has no CYA and very little FC and any it does have will be gone in an hour.
First you raise FC to 3 with bleach. Or get pH to 7.2>7.8. Doesn't really matter which.
Next you Measure out enough CYA to get to 60, unless you're absolutely positive about your pool's volume. Then you can aim for 70. Put in into hole-less socks or nylons and tie it shut and set it in the skimmer or dangle it in front of a return so lots of water hits it.
Step three is to fix FC or pH whichever you didn't do already. The first chemical had plenty of time to mix while you were fumbling with the CYA.
Step four, let the kids in.

You'll need to add bleach every day and as the sock dissolves, raise FC. It's straight math -- if half the sock is gone, CYA is half your target and you use that number in the [FC/CYA]chart [/FC/CYA]to pick your new target. Remember you're a bleach pool at the moment.

You'll be testing things (except CYA) daily and trying to get everything balanced. A day after the CYA is all dissolved, you can test it and make sure you reached target. Any time in there you can add salt. It's more fun to let the kids in while you do it. They'll mix it up great and have a blast.

When the CYA and salt are all dissolved, you can stop with the bleach and turn on the SWG.

 

[chris87]

I'm assuming you want it swimmable in a hurry, maybe some whiny kids begging to get in.

Test pH, TA, and CH. You know that tap water has no CYA and very little FC and any it does have will be gone in an hour.
First you raise FC to 3 with bleach. Or get pH to 7.2>7.8. Doesn't really matter which.
Next you Measure out enough CYA to get to 60, unless you're absolutely positive about your pool's volume. Then you can aim for 70. Put in into hole-less socks or nylons and tie it shut and set it in the skimmer or dangle it in front of a return so lots of water hits it.
Step three is to fix FC or pH whichever you didn't do already. The first chemical had plenty of time to mix while you were fumbling with the CYA.
Step four, let the kids in.

You'll need to add bleach every day and as the sock dissolves, raise FC. It's straight math -- if half the sock is gone, CYA is half your target and you use that number in the [FC/CYA]chart [/FC/CYA]to pick your new target. Remember you're a bleach pool at the moment.

You'll be testing things (except CYA) daily and trying to get everything balanced. A day after the CYA is all dissolved, you can test it and make sure you reached target. Any time in there you can add salt. It's more fun to let the kids in while you do it. They'll mix it up great and have a blast.

When the CYA and salt are all dissolved, you can stop with the bleach and turn on the SWG.

Thank you so much. This is exactly what I needed to know. I really appreciate it.

 

[BoDarville]

Richard and I are essentially saying the same thing. Since I have it written up, I'll post - if nothing else, it is validation that our recommendations are consistent.

1. Make sure pH is between 7.2 and 7.8. Adjust if needed.
2. Add 3 ppm chlorine (using liquid bleach) to the water and maintain at that level until you get some CYA in there. You will need to manually maintain and add chlorine until the CYA is dissolved and you get some salt in there to turn on the SWG. Until you have the SWG up and running, dose FC according to the Non-SWCG Pools table in the Chlorine CYA Chart.
3. Add CYA using granular CYA. Since you have a SWG pool, I would start with 60ppm and see how that works for you. With CYA, it is always better to start low and add more if needed than it is to start too high. It will take a few days or so for the granular CYA to dissolve.
4. Add the recommended amount of salt.
5. After adding salt and the CYA is dissolved, turn on the SWG and monitor chlorine levels (see Chlorine CYA Chart) - at this point, refer to the SWCG table. If the chlorine level drops, and testing confirms that salt levels and CC are in the recommended range, you can add more CYA if needed to reduce chlorine loss to sunlight.