First Time Slam Help

Lucy04

Member
Jul 19, 2021
19
Alberta
Hey, I'm a first time pool owner and cannot get my cc numbers under control. I have tried adding chlorine/shocking etc and they just keep raising. So I have decided it is time to SLAM my pool. I am currently partially draining the pool to deal with high CYA levels. I have a couple questions before I start:

1. I have a taylor dpd test kit, but my chlorine measurement only go up to 10 (The is maybe the difference between a FAS-DPD and a DPD?). How do I dilute the sample so I can monitor SLAM level FC?

2. I have typically used stabilized chlorine (as this is what the pool guy sells me) but this causes me problems with my cya levels and I understand that I can use inexpensive bleach instead? Other than making sure to add it slowly in front of the return, is there anything else I need to be aware of?

3. If the slam chlorine calculator says I need to add 6 jugs of bleach, I add them all at the same time? And then wait an hour, measure FC, and add more to bump FC levels back up to SLAM levels?

4. My PH is 7.4. I saw recommended is 7.2, do I need to use an acid reducer to drop it before I can begin?

Thanks so much for any help. I'm a little terrified I'm going to make things worse and wreck some pool equipment....

Brooklyn
 
Hey Lucy and Welcome !!!
. I have a taylor dpd test kit, but my chlorine measurement only go up to 10 (The is maybe the difference between a FAS-DPD and a DPD?). How do I dilute the sample so I can monitor SLAM level FC?
you need the DPD powder kit. The regular drop test is not accurate over 5ppm and you will be too far out of whack diluting the sample to read over 10. Order one up, Lower you ph to 7.2 and SLAM Process
Other than making sure to add it slowly in front of the return, is there anything else I need to be aware of?
nope !! Pour a pencil sized stream in front of a running return (jet) to save your clothes from impromptu polka dots. Ask me how I know. :)
As you’ve found the powders and tabs are stabilized with either CYA or calcium and not sustainable for full time use.
3. If the slam chlorine calculator says I need to add 6 jugs of bleach, I add them all at the same time? And then wait an hour, measure FC, and add more to bump FC levels back up to SLAM levels?
Test every 2 hours and add per poolmath from your current reading to SLAM level. (40% of CYA).
4. My PH is 7.4. I saw recommended is 7.2, do I need to use an acid reducer to drop it before I can begin
Actually scrap the above PH adjustment if you’d like. 7.4 is close enough. When the FC is 10 or above it makes the PH test wonky. So as long as you’re a bit on the lower side you have a week or two while you can’t accurately test the PH.
Thanks so much for any help. I'm a little terrified I'm going to make things worse and wreck some pool equipment....
We got you. Target for SLAM with no shortcuts or trying to do some self invented super SLAM. You can even swim up to and including SLAM levels once you can see the bottom for swimmer safety. You’re equipment is much tougher than you are. It’ll be fine.
 
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Welcome to TFP! :wave: As you will soon see, there are lots of folks here to help you with your SLAM Process. Just let us know.

 
Thanks! One more question, the pool store (before I stopped listening to them) gave me oxidizing shock that contains Pentapotassiumbis(peroxymonosulfate) bis(sulphate). I understand that this can interfere with TC readings from reagent #3. If this was added 3 days ago, could it still be interfering?
 
Hey Lucy and Welcome !!!

you need the DPD powder kit. The regular drop test is not accurate over 5ppm and you will be too far out of whack diluting the sample to read over 10. Order one up, Lower you ph to 7.2 and SLAM Process

nope !! Pour a pencil sized stream in front of a running return (jet) to save your clothes from impromptu polka dots. Ask me how I know. :)
As you’ve found the powders and tabs are stabilized with either CYA or calcium and not sustainable for full time use.

Test every 2 hours and add per poolmath from your current reading to SLAM level. (40% of CYA).

Actually scrap the above PH adjustment if you’d like. 7.4 is close enough. When the FC is 10 or above it makes the PH test wonky. So as long as you’re a bit on the lower side you have a week or two while you can’t accurately test the PH.

We got you. Target for SLAM with no shortcuts or trying to do some self invented super SLAM. You can even swim up to and including SLAM levels once you can see the bottom for swimmer safety. You’re equipment is much tougher than you are. It’ll be fine.
Thanks for the help! Unfortunately I can’t find a fas-dpd powder test kit where I live. Or online that ships to Canada. Any tips?
 
Unfortunately I can’t find a fas-dpd powder test kit where I live.
See these threads from members in Canada. Check to be sure it is still valid.

Poolsupplyhaus.ca (by Ottawa Pool Works) have the Talyor K2006 for sale at $148.35 and they can ship within Canada. If you are in Ottawa, you can pickup, the shipping fee to Southwestern Ontario is very reasonable for less than $14, they also supply reagents too. The customer service is very helpful and answer questions very promptly.[6]
 
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This one is recent from this season for 2 of our members :
 
Thanks for the tip on tftestkits.net. I'm 1hr from the border and usually just ship to montana and drive down. This border closure is killing my retail options!

So some more background:

After fighting with high cc and low fc for weeks, and adding lots of $$$ chemicals recommended by the pool store with no change and added problems (high CYA etc) During a partial refill to fix the CYA numbers, I finally figured out (thanks to this forum!!!!) that my problem was an algae colony behind my pool light. I pulled out the light, cleaned out all the algae, vacuumed up all the debris and then cleaned my filters (which had taken on a slightly greenish hue) and pump housing.

The water is now crystal clear, but the FC will not go up. I recognize I have residual algae in the pool and need to slam, which I will do as soon as I can get my hands on a fas-dpd kit.

My current numbers:

PH 7.4
FC 1 - this is after adding 2 jugs of clorox last night
TC 6
CYA 57
TA 125

In the meantime:

1. Is the pool swimmable? If my cc is very high, does that make it unsafe?
2. Until I can slam do I just continue to add 2 jugs of bleach each day? That seems expensive.
3. Do I need to chemically "treat" the cartridge filters are will the chlorine take care of that?
4. Am I best to leave the light detached and dangling in the pool while I slam to make sure the chlorine can get at it?

Thanks so much!
 

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1 - Normally yes, although that elevated CC tells us you have a bunch of organics trying to get oxidized. If you are able to get the FC up to at least 5 ppm, I would do that now.
2 - Just add one gallon per day for now.
3 - No need to do anything specific to the filter at this time.
4 - Yes. Just place the light on the decking if it will reach and make sure the power/breaker if OFF.
 
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Thanks! I added another gallon of clorox concentrated and my FC barely went up. It's now ~2ppm. I'm feeling like if I have to add 3 gallons of chlorine a day to stay ahead of the organics that are eating it, then why not take my chances with a blind slam (or at least a diluted dps) and throw in all 10 gallons at once?
 
Update: apparently the clorox from costco I added has chloromax which is a no-no. How screwed am I? I am ready to tear my hair out with this pool. Im in alberta, so pools are not super common and I cannot find regular liquid chlorine ANYWHERE. And now the majority of the bleach doesn't list a concentration on it, or has stupid additives. We should have built a pickleball court instead!
 
How screwed am I?
Cloromax is chlorine resistant polymer. It may foam your water. It may reduce your filters effectiveness. It may create a scum line at the waterline.

It is not the end of the world, but it is not recommended for continuous use.
 
Update: apparently the clorox from costco I added has chloromax which is a no-no. How screwed am I?
A few jugs never hurt anybody. Just like powdered shock and tabs, prolonged use is a problem for everybody, But every pool has its own threshold. Is 25 gallons your threshold ? 50? Beats me. But you’re fine for now. Find another source and you have us for moral support because it hasn’t been easy to do so. :)

Ive read a lot about Canadian Tire having pool supplies. Have you checked them out ?
 
Thank you @Newdude and @mknauss. I also have a phosphate reading of 765ppm, should I use a phos clense or wait until after slamming? All visible algae has been removed. Also, if I have to add 3 gallons of bleach a day to keep the fc level at 1, it seems to make more sense to just dump 10 gallons in at once and take my chances with a blind /diluted dps SLAM until my fas-dps test kit can come?
 
Phosphates are of no consequence to the majority of pool owners. If that level is correct, it is of no issue. You need multiple 1000's of ppb to be an issue.

You are welcome to add chlorine in any amounts you wish. Going above SLAM level based on your CYA can damage your liner. We cannot recommend adding large amounts of chlorine without accurate test data.
 
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