Become a TFP Supporter Pool Math Forum Rules Pool School
Page 1 of 2 12 LastLast
Results 1 to 20 of 28

Thread: SLAM Clarification

  1. Back To Top    #1

    Join Date
    Apr 2015
    Location
    South Central PA
    Posts
    296

    SLAM Clarification

    Hi,
    I got my pH at 7.5 and CYA 35, so I'm going to start SLAM. Never having done this before, I plan on adding 3 jugs of bleach (FC=1 to FC=14) and re-checking an hour later. I will be doing this after work, so I have about 4 hours until dark....My question is, how much do I have to stay on top of any chlorine dissapation? If I'm constantly adding bleach to maintain the shock level, do I have to keep doing it into the night, or will the effectiveness of what I did remain until the next day....I'm really trying to understand how important the timing is. The pool water is very clear, but I have very little FC (the water barely turns pink when adding the FAS/DPD powder)

    Thanks

    20000 gal
    Vinyl Liner
    DE Filter

  2. Back To Top    #2
    Patrick_B's Avatar
    Join Date
    Jun 2011
    Location
    Midland TX
    Posts
    15,001

    Re: SLAM Clarification

    Good questions, easy answers.

    You stay on the dosing and retesting as often as you possibly can. Every couple of hours at first. You don't have to stay up all night, but first thing next morning, check it. To find out if the doses hold, you'll have to determine that from testing. The goal, is to never let the FC drop below SLAM value for your Cya. Get as close to that as possible. When you dose, be careful to choose the right amount, but shoot for a few PPM higher than target. Say 24 IF your target is 20. That will give you a tiny extra, and at first, it may be consumed rapidly.
    TFP Moderator
    Essential Links:
    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

  3. Back To Top    #3
    Mod Squad tim5055's Avatar
    Join Date
    May 2014
    Location
    Columbia, SC
    Posts
    8,495

    Re: SLAM Clarification

    To add, don't get caught in the trap some fall into - if just a little more chlorine helps, a lot will be great. Nope, it doesn't work that way Just overshoot a little. Too much may damage equipment or fade your liner.

    You also said "I have about 4 hours until dark". You can continue the SLAM after dark, in the rain any time at all. Don't just stop because it gets dark. After dark you no longer have any loss to the Suns UV rays, so every drop you put in after dark is working on the algae. So during the evening at the end of each TV show go out and test the water and adjust the FC back up......
    TFP Moderator 39 X 18 23,000(ish) freeform gunite; built 2007ish; Pentair Triton II TR100 600lb Sand filter; 2 HP Pentair pump with 2.2 HP AO Smith single speed motor; 2 skimmers, 1 main drain, 4 returns w/waterfall, Stenner 45MHP2 3GPD running@ 60% - 15 gal Tank; heated by the sun CYA 200+ when I started - 50 now. Dolphin Supreme M5 Pool Cleaner. Hot Springs SX Spa, 285 gallon

  4. Back To Top    #4
    Mod Squad JVTrain's Avatar
    Join Date
    Feb 2014
    Location
    Central Minnesota
    Posts
    5,079

    Re: SLAM Clarification

    And... if your schedule allows, keep dosing and testing after dark. No sun means no chlorine is lost to sunlight! Don't lose any sleep over it pulling an all-nighter or anything though. Ideally, you'd be testing/dosing every hour until the SLAM is complete, but we've all got lives and the SLAM will progress as long as your testing and dosing several times per day and keeping the FC near SLAM level. It's OK to go 1-2 FC over the recommended SLAM target if you're not going to be able to dose for a longer period (sleep, work, etc.).

    When you get a chance, add the details of your pool to your forum signature. That way they're always there so that folks can more easily help you out. To change your profile and/or signature, select "Settings" (top right under Pool School button). Scroll down (left side) to "My Settings" & select Edit Profile or Edit Signature.
    Joel - TFP Moderator - Minnesota - **Become a TFP Supporter!** Helpful Links: ABCs of Pool Water Chemistry - SLAM Procedure - Chlorine/CYA Chart
    40x20 Pool: 32K Gallons * Vinyl * Bleach Chlorination * Hayward S270T Sand Filter * Pentair SuperFlo 1 HP * Teledyne/Laars Heater * AquaVac Tigershark * TF-100 w/ SpeedStir
    Isolated Spa - 345 Gallons

  5. Back To Top    #5
    Mod Squad woodyp's Avatar
    Join Date
    Apr 2010
    Location
    East Texas
    Posts
    9,000

    Re: SLAM Clarification

    That "light pink" syndrome can occur when the water is still a bit chilly too. Take a sample inside, let it warm and see if you have a difference. WHY are you slamming?
    16x32x52" Steel Cornelius Miramar AGP Vinyl liner 13,100 gal. Buried 2 ft.
    2 Speed Hayward Power-Flo Matrix 85 g.p.m. 22" 250lb. sand filter hard plumbed
    Pool Rover Jr., Pool Blaster Max, Diver Dave TF100 Test Kit/Speed Stir
    Margaritaville Frozen Concoction Maker, Liqour Chiller, & Drink Mixer & Party Tub----Collect 'um all!

  6. Back To Top    #6

    Join Date
    Apr 2015
    Location
    South Central PA
    Posts
    296

    Re: SLAM Clarification

    Thanks for all the input. The reason I'm slamming is that I want to transition from the tablets to liquid chlorine, and my FC is extremely low....is SLAMMING in this case not appropriate? I'm learning more and more as I go alone, but previously I added liquid chlorine a few gallons at a time (probably a total of 5 gallons to this point), not actually following SLAM as it turns out, but it did very little to FC, ant the auto chlorinator is doing very little as well. Should I be SLAMMING?

  7. Back To Top    #7
    Mod Squad tim5055's Avatar
    Join Date
    May 2014
    Location
    Columbia, SC
    Posts
    8,495

    Re: SLAM Clarification

    Quote Originally Posted by 440dodge440 View Post
    Thanks for all the input. The reason I'm slamming is that I want to transition from the tablets to liquid chlorine, and my FC is extremely low....is SLAMMING in this case not appropriate? I'm learning more and more as I go alone, but previously I added liquid chlorine a few gallons at a time (probably a total of 5 gallons to this point), not actually following SLAM as it turns out, but it did very little to FC, ant the auto chlorinator is doing very little as well. Should I be SLAMMING?
    Unless you have something growing in the water (visable algae, cloudy water, fail OCLT) there is no need to SLAM. Just stop using pucks and use liquid each day.

    Are there still tabs in your feeder?

    Can you give us a full set of test results?

    Have you conducted an Overnight FC Loss Test (OCLT)?

    Sorry, lots of questions but we want to direct you down the right path.

    How much Pool School have you read? Start with these:
    ABCs of Water Chemistry
    Recommended Pool Chemicals
    How to Chlorinate Your Pool
    TFP Moderator 39 X 18 23,000(ish) freeform gunite; built 2007ish; Pentair Triton II TR100 600lb Sand filter; 2 HP Pentair pump with 2.2 HP AO Smith single speed motor; 2 skimmers, 1 main drain, 4 returns w/waterfall, Stenner 45MHP2 3GPD running@ 60% - 15 gal Tank; heated by the sun CYA 200+ when I started - 50 now. Dolphin Supreme M5 Pool Cleaner. Hot Springs SX Spa, 285 gallon

  8. Back To Top    #8

    TFP Guide

    Kiss4aFrog's Avatar
    Join Date
    May 2013
    Location
    Hudson, WI
    Posts
    2,602

    Re: SLAM Clarification

    If the water looks good, testing shows less than .5 CC and you can pass the OCLT then you have no need to spend the money on extra bleach to SLAM. Just start using bleach to reach the proper FC level for your CYA and maintain.
    '70s IG Vinyl 32K gal, Lazy L, Hayward SuperPump 1.5hp 120V, S240 Sand Filter W/DE
    Solar Blanket, Well Water, Borax Added, TF-100 tester. ? too cold
    1979, 275gal Conway Emerald Spa P-100-2, ES-2 Spa Pack, bromine floater, indoor
    TF-100, Best test kit - TFTestkits.net
    Please help keep the lights on, become a TFP Supporter!

  9. Back To Top    #9
    Mod Squad woodyp's Avatar
    Join Date
    Apr 2010
    Location
    East Texas
    Posts
    9,000

    Re: SLAM Clarification

    Seems to me than an overnight chlorine loss test is in order here (OCLT). If you're good there---your water is already clear and you have no visible signs of algae---no reason to SLAM just to "convert". FULL test results please!
    16x32x52" Steel Cornelius Miramar AGP Vinyl liner 13,100 gal. Buried 2 ft.
    2 Speed Hayward Power-Flo Matrix 85 g.p.m. 22" 250lb. sand filter hard plumbed
    Pool Rover Jr., Pool Blaster Max, Diver Dave TF100 Test Kit/Speed Stir
    Margaritaville Frozen Concoction Maker, Liqour Chiller, & Drink Mixer & Party Tub----Collect 'um all!

  10. Back To Top    #10

    Join Date
    Apr 2015
    Location
    South Central PA
    Posts
    296

    Re: SLAM Clarification

    I apologize if I'm not understanding well, but this is my first year with a pool, so I'm not real clear on all of the tests....I read about the OCLT, and I did the FAS/DPD test (though not comparing overnight), and the test shows about 1 ppm of FC...the OCLT requires no more than 1ppm loss of FC, correct? So if I'm starting with (barely) 1ppm, I'm not really going to know if I pass or fail. I guess I thought SLAM would bring my FC level up to a point where I could detect a difference in the OCLT. It would be great if I don't need to SLAM, but how do I bring the FC level up -should I use pool math and add liquid chlorine to go from FC=1 to FC=4.5 (target in my case), and keep adding to try to maintain that? I will do another CC test- I did one the other night, and I got between .5 and 1 (depending on when I actaully determined when the water cleared), but it was the first one I did and I was unclear on what I was actually testing- I was just following instructions....

  11. Back To Top    #11
    Mod Squad JVTrain's Avatar
    Join Date
    Feb 2014
    Location
    Central Minnesota
    Posts
    5,079

    Re: SLAM Clarification

    Typically the OCLT is performed at higher (SLAM) levels. In your case, I would use Pool Math to try to bring FC up to 6 or a bit more. Once you've added bleach, let circulate for and hour then retest to get your starting point for the OCLT. Test FC in the morning. It's best to do your pre-OCLT after sundown and your morning test before/close to sun up.
    Joel - TFP Moderator - Minnesota - **Become a TFP Supporter!** Helpful Links: ABCs of Pool Water Chemistry - SLAM Procedure - Chlorine/CYA Chart
    40x20 Pool: 32K Gallons * Vinyl * Bleach Chlorination * Hayward S270T Sand Filter * Pentair SuperFlo 1 HP * Teledyne/Laars Heater * AquaVac Tigershark * TF-100 w/ SpeedStir
    Isolated Spa - 345 Gallons

  12. Back To Top    #12
    Mod Squad tim5055's Avatar
    Join Date
    May 2014
    Location
    Columbia, SC
    Posts
    8,495

    Re: SLAM Clarification

    How often are you adding chlorine? With a CYA of 40 you should never let your FC drop below 3. To keep it above 3 we generally target 5 so that as the sun consumes it during the day it does not go below 3.

    As to your CYA, the scale on the tube is not linear, so you can't say half way between 30 & 40 is 35, just assume 40 for chlorine additons.
    TFP Moderator 39 X 18 23,000(ish) freeform gunite; built 2007ish; Pentair Triton II TR100 600lb Sand filter; 2 HP Pentair pump with 2.2 HP AO Smith single speed motor; 2 skimmers, 1 main drain, 4 returns w/waterfall, Stenner 45MHP2 3GPD running@ 60% - 15 gal Tank; heated by the sun CYA 200+ when I started - 50 now. Dolphin Supreme M5 Pool Cleaner. Hot Springs SX Spa, 285 gallon

  13. Back To Top    #13

    Join Date
    Apr 2015
    Location
    South Central PA
    Posts
    296

    Re: SLAM Clarification

    I had the auto chlorintor with tablets on full until a few days ago- I was concerned about getting the CYA too high, so I turned it down to 1/4, and will close it when I get this liquid bleach thing figured out (prior to OCLT). This is all that's adding chloring at this point. The pool was just opened for the season on 4/27 after being closed in August by the previous owners. I just got the pH to 7.5, so I was planning on the transition to liquid chlorine. I'm pretty sure FC hasn't been above much more than 1 since it was opened for the season. I will target FC=6 after sundown to get the OCLT start point. Thanks for all the advice- any other tip/help is also appreciated!!

  14. Back To Top    #14

    TFP Guide
    Mr Bruce's Avatar
    Join Date
    Mar 2014
    Location
    Greenville, SC
    Posts
    1,798

    Re: SLAM Clarification

    I have a tip. Print this out

    http://www.troublefreepool.com/conte...art-slam-shock

    and tape it to the inside of your test kit or inside a cabinet door where you test. I've been doing this over a year and I still look at it a lot to determine where I need to be.
    32K gallon Plaster - 1hp Hayward 2 speed Super Pump - Hayward S200 Sand Filter - TF100XL
    Test Kits - Pool Math - Chlorine/CYA/Target/Slam Chart

  15. Back To Top    #15

    TFP Guide

    Kiss4aFrog's Avatar
    Join Date
    May 2013
    Location
    Hudson, WI
    Posts
    2,602

    Re: SLAM Clarification

    440Dodge, please take the time to add your pool equipment info to your signature as outlined here: http://www.troublefreepool.com/conte...etting-started
    '70s IG Vinyl 32K gal, Lazy L, Hayward SuperPump 1.5hp 120V, S240 Sand Filter W/DE
    Solar Blanket, Well Water, Borax Added, TF-100 tester. ? too cold
    1979, 275gal Conway Emerald Spa P-100-2, ES-2 Spa Pack, bromine floater, indoor
    TF-100, Best test kit - TFTestkits.net
    Please help keep the lights on, become a TFP Supporter!

  16. Back To Top    #16
    Mod Squad tim5055's Avatar
    Join Date
    May 2014
    Location
    Columbia, SC
    Posts
    8,495

    Re: SLAM Clarification

    Quote Originally Posted by 440dodge440 View Post
    I had the auto chlorintor with tablets on full until a few days ago- I was concerned about getting the CYA too high, so I turned it down to 1/4, and will close it when I get this liquid bleach thing figured out (prior to OCLT). This is all that's adding chloring at this point. The pool was just opened for the season on 4/27 after being closed in August by the previous owners. I just got the pH to 7.5, so I was planning on the transition to liquid chlorine. I'm pretty sure FC hasn't been above much more than 1 since it was opened for the season. I will target FC=6 after sundown to get the OCLT start point. Thanks for all the advice- any other tip/help is also appreciated!!
    Great. As a little background the OCLT is a way of determining if anything is growing in the water. Only two things cause your FC level to go down - UV from the sun (that is what CYA helps protect against) and organics being oxidized by the chlorine. If you take a reading after the sun sets and then a second one before the sun get on the pool you can see if organics are present. Anything over a 1ppm loss in FC overnight tells us that you got something in the water.
    TFP Moderator 39 X 18 23,000(ish) freeform gunite; built 2007ish; Pentair Triton II TR100 600lb Sand filter; 2 HP Pentair pump with 2.2 HP AO Smith single speed motor; 2 skimmers, 1 main drain, 4 returns w/waterfall, Stenner 45MHP2 3GPD running@ 60% - 15 gal Tank; heated by the sun CYA 200+ when I started - 50 now. Dolphin Supreme M5 Pool Cleaner. Hot Springs SX Spa, 285 gallon

  17. Back To Top    #17
    Defgufman's Avatar
    Join Date
    Mar 2015
    Location
    Savannah GA
    Posts
    577

    Re: SLAM Clarification

    Quote Originally Posted by 440dodge440 View Post
    Hi,
    I got my pH at 7.5 and CYA 35, so I'm going to start SLAM. Never having done this before, I plan on adding 3 jugs of bleach (FC=1 to FC=14) and re-checking an hour later. I will be doing this after work, so I have about 4 hours until dark....My question is, how much do I have to stay on top of any chlorine dissapation? If I'm constantly adding bleach to maintain the shock level, do I have to keep doing it into the night, or will the effectiveness of what I did remain until the next day....I'm really trying to understand how important the timing is. The pool water is very clear, but I have very little FC (the water barely turns pink when adding the FAS/DPD powder)

    Thanks

    20000 gal
    Vinyl Liner
    DE Filter
    How did you decide on 3 gallons of bleach? I would turn off the chlorinator, and add 1 gallon of 8.25% bleach to your 20000 gal pool. If the water is clear, and at a cya of 35, you need between 4 and 5 FC to maintain it.
    Inground 13,200 gal Vinyl, Pentair 3/4 hp pump, Pentair Sand Dollar filter, Polaris 280

    Pool School, Pool Math, CYA to FC ratio chart, Testing Kits

  18. Back To Top    #18
    Mod Squad tim5055's Avatar
    Join Date
    May 2014
    Location
    Columbia, SC
    Posts
    8,495

    Re: SLAM Clarification

    Quote Originally Posted by Defgufman View Post
    How did you decide on 3 gallons of bleach? I would turn off the chlorinator, and add 1 gallon of 8.25% bleach to your 20000 gal pool. If the water is clear, and at a cya of 35, you need between 4 and 5 FC to maintain it.
    Actually thngs have changed further down in the thread. He is trying to determine if he as an organic issue that needs a SLAM, so he is bringing the FC up tonight to complete an OCLT.
    TFP Moderator 39 X 18 23,000(ish) freeform gunite; built 2007ish; Pentair Triton II TR100 600lb Sand filter; 2 HP Pentair pump with 2.2 HP AO Smith single speed motor; 2 skimmers, 1 main drain, 4 returns w/waterfall, Stenner 45MHP2 3GPD running@ 60% - 15 gal Tank; heated by the sun CYA 200+ when I started - 50 now. Dolphin Supreme M5 Pool Cleaner. Hot Springs SX Spa, 285 gallon

  19. Back To Top    #19

    Join Date
    Apr 2015
    Location
    South Central PA
    Posts
    296

    Re: SLAM Clarification

    Yes, the 3 gallons was when I thought I has to SLAM it. I will be adding about 1 gallon after sunset, check FC and CC, and re-check in the morning.
    20000 gallon vinyl liner in ground pool
    16' X 34' rectangular diving pool
    Hayward Pro Grid DE Filter
    Hayward 1 hp Super Pump
    TF-100 Test Kit Stenner 45MPHP10

  20. Back To Top    #20
    Patrick_B's Avatar
    Join Date
    Jun 2011
    Location
    Midland TX
    Posts
    15,001

    Re: SLAM Clarification

    Sounds like a good chance no SLAM will be needed, but you asking about it is good. You're on the right track now man.
    TFP Moderator
    Essential Links:
    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •