Curious about recommended SLAM values

kne

Gold Supporter
Jun 26, 2015
428
Concord, CA
Pool Size
7600
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-30 Plus
Purely curiosity, not questioning the TFP Gods! I do as you say.
Regarding SLAM, does more chlorine mean stronger fighting power or is it more of a less chance of going under the minimum chlorine requirements.
If my CYA is 30 and my Recommended FC is 2.0 – 6.0 but SLAM target is 12. If hypothetically I was to keep it at a constant 7.5 would that fight the algae the same as at a 12?
 
Purely curiosity, not questioning the TFP Gods! I do as you say.
Regarding SLAM, does more chlorine mean stronger fighting power or is it more of a less chance of going under the minimum chlorine requirements.
If my CYA is 30 and my Recommended FC is 2.0 – 6.0 but SLAM target is 12. If hypothetically I was to keep it at a constant 7.5 would that fight the algae the same as at a 12?
Never an issue to ask a question!!!

Use the SLAM Process process when you have algae. If you don't have algae, keep it at the top of the recommended range.

Above a certain level of HOCl in the water and you kill algae. When you have higher CYA, you need higher FC to maintain a HOCl level high enough to kill algae. Hence the SLAM level recommendations are to maintain levels high enough to kill all the algae.

Do you have algae? or were you asking if you kept your pool at 7.5 would that HOLD OFF GETTING algae better than keeping 2-6 FC?
 
  • Like
Reactions: Newdude
Do you have algae? or were you asking if you kept your pool at 7.5 would that HOLD OFF GETTING algae better than keeping 2-6 FC?
I have algae, I am doing a SLAM (recommended TFP levels). As I was measuring out the chlorine every couple hours to keep at 12 I was wondering, why 12? I know if I went to like 20 with my CYA it would knock out the algae, but be too strong, bleached liner, etc. But if I was to keep it at, let's say 9, would that kill the algae?
 
There’s nothing magical about the 40% FC/CYA ratio that TFP uses for its SLAM criteria. It’s a balance between having enough chlorine in the water to really overwhelm the algae versus using a level that safe for people and equipment. The higher the FC level, the higher the intrinsic chlorine loss rate (loss not associated to disinfection). So, at some point it makes no sense to add higher levels of FC as you’re only wasting it. That “line in the sand” for TFP is 40%.
 
But if I was to keep it at, let's say 9, would that kill the algae?
It will, but will take longer. It'll be no worse than people who are busy and simply can't babysit the FC levels all day. But if it drags on for a week more, that's alot of jugs used for not maintaining the 12.
 
  • Like
Reactions: Mdragger88 and kne
Funny story this, but the levels deemed prudent to combat algae were "developed" empirically decades ago, then "confirmed" on paper therafter. It was experienced based, and continues to be thus.

If I say more my post gets unceremoniously deleted...
That’s fair. It started out as a “Best Guess” CYA chart, based on experience, but was refined to align with chemical principles.

None of that makes it any less valid.

 
None of that makes it any less valid
+1. Pretty much anything that ever was started as a 'best guess'. In the end, with years and years of testing in the real world, the best guess.......... was in fact, and simply became the best.
 
What's the difference between SLAM and Shock?

SLAM is a process and procedure. The acronym is short for Shock Level And Maintain.

Shock is a product sold in stores which is nothing more than a source of chlorine put in a fancy package.

Shock levels are FC concentrations above a certain threshold. For TFP, shock levels of chlorine are set to 40% of CYA concentration.
 
  • Like
Reactions: Decoy205 and xDom

Enjoying this content?

Support TFP with a donation.

Give Support
SLAM is a process and procedure. The acronym is short for Shock Level And Maintain.

Shock is a product sold in stores which is nothing more than a source of chlorine put in a fancy package.

Shock levels are FC concentrations above a certain threshold. For TFP, shock levels of chlorine are set to 40% of CYA concentration.
If a pool with an SWG needed to SLAM would they rely on the SWG to bring the chlorine level up or do they need to add chemical chlorine?
 
If a pool with an SWG needed to SLAM would they rely on the SWG to bring the chlorine level up or do they need to add chemical chlorine?

You have to manually chlorinate to SLAM a pool. No SWG can handle that kind of rise. You could leave the SWG running if you want, it most shut it off. It needs to be shut off when doing an OCLT to determine if the SLAM is complete or not.
 
  • Like
Reactions: xDom
That’s fair. It started out as a “Best Guess” CYA chart, based on experience, but was refined to align with chemical principles.

None of that makes it any less valid.

Just as Pinocchio learned to speak truth, do good and thus become a real boy, enough anecdotes become “data.” :)
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.