First SLAM Questions

[NYAVGUY]

Hi - I am doing my first SLAM since following the TFP method. Long Story short...a lot of rain and me miscalculating chlorine consumption under my mesh cover this year led to an opening algae bloom. A flock of birdz landing in what they though was a pond probably didn't help....

I started out by putting 2-gallons of 12.5% which was about what pool math said I needed to get to SLAM level of 16. After 6-hours FC only measured 7 with CC1.0, so I put in another Gallon. Following morning I was up to FC 11, CC .5. Since then the pool seems to be consuming a full gallon of FC every 8-12 hours as the highest result I have gotten is FC 11.5. The green cloudiness is gone and now it is just cloudy. I have vacuumed twice with skimmer sock, and been brushing walls and crevaces.

Questions:.
1. Should I be testing 1-2 hours after adding chlorine to confirm I am actually getting to SLAM level?
2. Could the 12.5% shock I bought at ACE Hardware be less than advertised?
3. I already started bringing the salt level up, when should I start brining the CYA levels up to TFP recommended levels?
4. Should I consider adding DE or buying a water clarifier to speed up the process if I am impatient and want it clear by the weekend?
5. Should I not backwash when pressure goes up 2-4 PSI as the extra debris in the sand filter will help clear up the cloudiness faster and let it get up higher?

Initial Test Results (TF-100 Pro) prior to SLAM:
FC - 0
CC- 0
pH - 7.5
CYA - 40
CH - 200
Salt - 2400
Temp - 56

 

[Texas Splash]

1. Should I be testing 1-2 hours after adding chlorine to confirm I am actually getting to SLAM level?

Tough to get time-specific. Everyone's schedule varies. But as time permits, test as much as needed to help maintain the proper FC level without huge drops. For some people that's twice a day, others might be 4.

2. Could the 12.5% shock I bought at ACE Hardware be less than advertised?

Less in strength? If it's advertised as 12.5%, it should be. However the Julian date on the bottle tells you when it was packaged. Older chlorine tends to get weaker.

3. I already started bringing the salt level up, when should I start brining the CYA levels up to TFP recommended levels?

Don't increase the CYA until you pass all 3 SLAM criteria.

4. Should I consider adding DE or buying a water clarifier to speed up the process if I am impatient and want it clear by the weekend?

No on the clarifier. Also no on the DE for now. Save any attempts to filter "dead" algae with DE until the very last.

5. Should I not backwash when pressure goes up 2-4 PSI as the extra debris in the sand filter will help clear up the cloudiness faster and let it get up higher?

Backwash when your filter pressure increases by about 25%. A slightly dirtier sand filter tends to grab more of hte finer stuff.

 

[NYAVGUY]

Thanks for the reply. I think all the Algae is pretty much dead now, just cloudy.

I think I will just wait and let the SLAM work like suggested.

I would like to add a little Calcium to up my CSI and then install my SWG for the season. Since my PH and Alkalinity was good prior to SLAM, I don't think the high Chlorine Levels will impact it now, correct? I have never had to acid wash my SWG since I keep my pool perfectly balanced and only install it in the spring once CSI is within range. I have a vinyl liner pool with fiberglass steps so follow fiberglass hardness recommendations.

 

[Texas Splash]

You can ignore the pH and TA testing until you finish the SLAM. Vinyl and fiberglass don't require CSI management, so unless you have a heater that requires it, you probably don't need to add calcium.