1st time SLAMMER and have some questions

Threekids03

Bronze Supporter
May 28, 2024
41
Pa
Pool Size
4700
Surface
Vinyl
Chlorine
Liquid Chlorine
I'm reposting in the hopes I get some hits.

I found TFP because I was worried about my non-existent FC and started reading here about the CYA/Chlorine relationship. I ordered the Taylor FAS-DPD kit and began draining my pool when the test revealed my CYA was really high. I got the CYA to 70 (could see the black dot at 70 but not 60) and began preparing to SLAM. I replaced my cartridge filter with a brand new one (the used one was bright green despite only being used 3 weeks this season) and vacuumed and brushed my pool. There was a small amount of sandy looking brown substance scattered around the bottom of my pool. It wasn't in shady areas, just scattered about, and unfortunately I didn't touch it to check if it felt sandy or slimy because I wasn't thinking algae at the time, the water had been crystal clear even before draining. Now I'm thinking I was on the verge of an algae bloom.

Last night I SLAMMED and tested the FC 30 min. after adding. My goal was 28 and I reached 22.5 with a CC of 2. (I may be underestimating my pool volume) I added more chlorine according to the calculator to bring it up to 28, but didn't test a 2nd time because I don't want to run out of reagent. (Last night I ordered a big bottle from Amazon). This morning my test showed FC 8 CC 1. I added chlorine but didn't retest afterward. I will do it again at noon and tonight as well.

Here are my questions.
1. I am soaking the original cartridge in filter cleaner - should I just throw it out?
2. At what point should I spray out the cartridge I'm using now...not sure if should stop the pump to do this?
3. Should I throw out the vacuum hose, head that used I to vacuum prior to SLAMMING? (because of 0 FC and potential algae) and should I throw out brushes and pole at the end of this?
4. Should I also be testing every time 30 min after I add chlorine to ensure I reach SLAM level or just at night and morning for the OCLT? (I plan to increase my pool volume setting next chlorine addition)

Thank you again in advance! I've suspected for a long time that something was wrong, but I really trusted my pool dealer. I've just always let him decide what I needed but never felt good about him brushing off my questions. I'm really getting an education here!
 
1. I am soaking the original cartridge in filter cleaner - should I just throw it out?
Depends on what chemicals had been added previously...i.e. did they gum the filters? Visually inspect, if they look clean use them and see if the pressure is consistent with new cartridges.
2. At what point should I spray out the cartridge I'm using now...not sure if should stop the pump to do this?
Put clean filters in, not pressure. When pressure rises 25%, clean them again.
3. Should I throw out the vacuum hose, head that used I to vacuum prior to SLAMMING? (because of 0 FC and potential algae) and should I throw out brushes and pole at the end of this?
No, just clean with some 10:1 Water:Bleach...good to go.
4. Should I also be testing every time 30 min after I add chlorine to ensure I reach SLAM level or just at night and morning for the OCLT? (I plan to increase my pool volume setting next chlorine addition)
No. Yes for OCLT. But if you can increase the frequency of checking and replacing it will go faster.
 
Thank you! The cartridge looked fine other than the green, it was only used previously part of last summer and this year. I will go and check the pressure now. Thanks! I'll soak everything, just hope the hose fills up with the bleach solution. Maybe I'll use it again too when the pool is done SLAMMING and FC is 10 to make sure it's blown out.
I'm leaving for a few days on Wednesday and hopefully slamming is done by then. Not sure what my FC should be before I leave? I can also leave a puck in the floater.
 
Throw the equipment in the pool and scrub them. Slam water will clean them up.

Raise your FC to SLAM level and float the pucks when you leave.
 
The SLAM instructions say to SLAM when "Loss of 1.0 ppm of FC overnight" and to finish the SLAM when "OCLT shows 1.0 ppm of loss or less". So is 1ppm loss ok or not? Sounds unacceptable in instructions of WHEN to SLAM but acceptable for when to FINISH SLAM ?
My SLAM goal is 28 with a CYA of 70. 1ppm FC is only .0357 percen of my goal which is much smaller than for someone with a much lower goal. Also leaves waaaay less room for error when testing.
Also, is it ok to clean my original cartridge in Pro Team Filter Magic or should I do bleach solution? It's already been soaking in the magic
 
The SLAM instructions say to SLAM when "Loss of 1.0 ppm of FC overnight" and to finish the SLAM when "OCLT shows 1.0 ppm of loss or less". So is 1ppm loss ok or not? Sounds unacceptable in instructions of WHEN to SLAM but acceptable for when to FINISH SLAM ?
My SLAM goal is 28 with a CYA of 70. 1ppm FC is only .0357 percen of my goal which is much smaller than for someone with a much lower goal. Also leaves waaaay less room for error when testing.
Also, is it ok to clean my original cartridge in Pro Team Filter Magic or should I do bleach solution? It's already been soaking in the magic
You start a SLAM when you have visible algae or fail an OCLT. You stop the SLAM when the FC loss overnight is 1.0ppm or less, AND you have 0.5CC or less, AND there is no visible algae dead or alive.
 
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Just rinsing your filter well is sufficient.
The 3 criteria to end the
SLAM Process are:
Crystal clear water (no recurrent algae dead or alive)
&
1ppm or less overnight fc loss
&
0.5 or less cc’s

All 3 must be true.
 
You start a SLAM when you have visible algae or fail an OCLT. You stop the SLAM when the FC loss overnight is 1.0ppm or less, AND you have 0.5CC or less, AND there is no visible algae dead or alive.
That's my point. An OCLT test says that it's unacceptable to have a loss of 1ppm so how is it acceptable to stop the SLAM at 1ppm?
 
You start a SLAM when you have visible algae or fail an OCLT. You stop the SLAM when the FC loss overnight is 1.0ppm or less, AND you have 0.5CC or less, AND there is no visible algae dead or alive.
That's my point. Everything else aside, a pool owner fails the OCLT if the FC loss is 1ppm but it's acceptable to stop the SLAM at FC loss of 1ppm?
 
Just rinsing your filter well is sufficient.
The 3 criteria to end the
SLAM Process are:
Crystal clear water (no recurrent algae dead or alive)
&
1ppm or less overnight fc loss
&
0.5 or less cc’s

All 3 must be true.
Thanks. I understand about the other criteria, I just don't understand how 1ppm loss is a failing OCLT but 1ppm loss is fine for stopping SLAM
 

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That's my point. An OCLT test says that it's unacceptable to have a loss of 1ppm so how is it acceptable to stop the SLAM at 1ppm?
I think youre conflating two separate things. You fail an OCLT if you lose more than 1ppm FC. The SLAM keeps going if you fail the OCLT.
 
My SLAM goal is 28 with a CYA of 70. 1ppm FC is only .0357 percen of my goal which is much smaller than for someone with a much lower goal. Also leaves waaaay less room for error when testing.

All true (except ".0357 percent", which I'm sure you meant to write as 3.57 percent). It's easier to SLAM at lower CYA concentrations. But it's not TERRIBLE to do it at 70:

a) Your numbers aren't THAT much different from others -- worst case, the ratio is 2:1 between your pool and a pool at the extreme low end of the scale at 30ppm CYA; for pools with CYA between 30 and 70, the ratio is closer to 1:1.

b) In my experience, the OCLT shows much more than 1.0ppm loss if algae is present, and there's an obvious step down to basically zero when the algae is eradicated. The "1.0ppm" threshold, as far as I can tell, really means "zero, but with some measurement error and the effect of normal non-algae FC usage (leaves, pollen, etc.) taken into account".
 
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All true (except ".0357 percent", which I'm sure you meant to write as 3.57 percent). It's easier to SLAM at lower CYA concentrations. But it's not TERRIBLE to do it at 70:

a) Your numbers aren't THAT much different from others -- worst case, the ratio is 2:1 between your pool and a pool at the extreme low end of the scale at 30ppm CYA; for pools with CYA between 30 and 70, the ratio is closer to 1:1.

b) In my experience, the OCLT shows much more than 1.0ppm loss if algae is present, and there's an obvious step down to basically zero when the algae is eradicated. The "1.0ppm" threshold, as far as I can tell, really means "zero, but with some measurement error and the effect of normal non-algae FC usage (leaves, pollen, etc.) taken into account".
Ok. Thank you for clearing that up! I pray I'm ok tomorrow
 
I might have missed it, but how does your water look today and why did you SLAM in the first place?

In my opinion, the eye test is the most important and the OCLT and CC tests are the last ones you do to end the SLAM once you have crystal clear water. If you have cloudiness, visible algae, etc. then its premature to do the OCLT and CC tests.
 
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I might have missed it, but how does your water look today and why did you SLAM in the first place?

In my opinion, the eye test is the most important and the OCLT and CC tests are the last ones you do to end the SLAM once you have crystal clear water. If you have cloudiness, visible algae, etc. then its premature to do the OCLT and CC tests.
My water was crystal clear but CYA was high and I wasn't able to hold FC. I never knew anything about CYA before i found this group but i knew something was wrong despite my pool dealer telling me i was fine with enzymes. When I drained the pool and took out the filter it was bright green...think I was on the verge of a bloom. I started the SLAM Sunday night. Yesterday morning my FC was 8. This morning it was 18. I'm SLAMMIMG every 2 hrs today.
 
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