New to TFP, about to start SLAM

Timmygreen

Active member
Apr 22, 2017
31
Yardley, PA
#1
Hi All. I am just about to open the pool from the winter storage (first time pool owner). I believe that the pool is green enough in color to SLAM right off the bat. I took my measurements with the Taylor 2006 and here is where I am at:

FC - 0
CYA - <20
TA - 100
PH - >8

So I plan on starting the filter, with the cartridges removed at first to circulate the water. I will vacuum the dirt and small debris to waste right away, and add the pool math calculated amount of dry acid (since I have some in already) to get the PH into the 7.2- 7.5 range. Once the PH is good, I plan to start adding bleach to begin the SLAM. Here are my questions:

1. Should I add the filter and add full DE once I start SLAM?
2. Do I need to add any CYA before the SLAM starts since the levels are very low? Weather looks like sunny and 70s in the daytime for the next week here in Pennsylvania.
3. If no CYA needed until after the SLAM, since I need to add about 8 lbs of it given my pool size, can I just add it all at once or should I do the sock method?

Thanks!!!
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#2
Timmy, you have the concept just about right. I might offer a couple more comments to help:
1. Yes, once you start the SLAM ensure the grids are in and loaded with DE. You'll go through DE from each backwash, but it's the nature of a DE filter as it catches the dead algae.
2. Before you add anymore stabilizer, try this: After the pH is lowered, increase FC to "10". Test it 10 minutes later just to ensure it's still above 5. If it is, then yes - increase CYA to "30 and increase FC to "12" and press-on with your SLAM. If your FC didn't hold after 10 minutes, repeat until it does before you add that stabilizer. Hope that makes sense.
3. When you finally do add stabilizer, use the sock-soaking method and squeeze it periodically. Yes, you can add it all at once no problem.

Hope that helps. Good luck!
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#4
So you are saying that there should be some level of CYA in the pool for SLAM?
Absolutely. CYA protects the FC (Free Chlorine/bleach) from the sun's UV. But please follow the notes above and do that 10-min test just to ensure FC will hold above 5 for 10 minutes. Once you do that, get the stabilizer soaking in a sock for a CYA target of "30" and increase FC to "12" and you're on your way. Make sure to review everything else on the SLAM page to ensure you are reminded of other things to do (brushing, filter cleaning, etc).
 

Timmygreen

Active member
Apr 22, 2017
31
Yardley, PA
#5
I am one day into SLAM, got the FC level up good, and came back down....no worries I know this will take some time...and alot of bleach!! My filter tho ( which was chemcially cleaned before starting SLAM)....keeps going from about 15 psi after backwash to above 30 in a couple hours. I keep backwashing, and adding more DE....Question is...at some point should I just break down filter and hose it down? Or is it normal to have to backwash a few times a day during a SLAM? Water was not that full of debree....
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#6
Your filter is doing it's job. :goodjob: It's collecting a ton of dead algae and anything else you're kicking-up into the water from brushing/sweeping. Remember that organic material is not always visible. It's a pain with all those backwashes, but it's doing what it should be. No need to disassemble yet unless you feel something wrong may have happened. If you have to leave the house for a while and are worried about pressure while you're gone, you can always place the filter on recirculate if you have a multiport valve. At least you'll keep the chlorine moving until you get back.
 

Timmygreen

Active member
Apr 22, 2017
31
Yardley, PA
#8
Ok 24 hours into SLAM, have added 16 gallons of bleach already, 6 a time, and cannot get FC above 2. Does this likely mean that I have ammonia in the pool? I did not get a CYA reading above 20 before starting, and havent added any yet. Pool is already relatively clear and see through water...
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
#9
It doesn't sound like you're doing the SLAM yet actually. Ammonia? It is very possible. That's what the 10-min drill above is all about. It is very important to continue that testing and adding of bleach every 10 min until the FC holds between 5-10. Only after passing that 10-min drill do you immediately add stabilizer for a CYA target of 30. Then the bleach (FC) will hold much better. But if it is indeed ammonia that is knocking-out your FC so quickly, you have to re-add FC at 10-min intervals. Once it holds though, you'll be okay.
 

Timmygreen

Active member
Apr 22, 2017
31
Yardley, PA
#10
Everything is going great with the SLAM. Getting ready to perform the overnight FC loss test soon...does it matter if the DE pump/filter is running overnight or not during the test?