Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 11 of 11

Thread: Should I SLAM?

  1. Back To Top    #1

    Should I SLAM?

    Hi everyone, thought pool season would never happen here in north/central Pa. I need to clarify a chemistry point. I opened yesterday and have the filter running. The chem is as follows:

    fc .5
    cc 1
    cya 0
    ph 7.5
    ta 140
    borates 80

    I plan on SLAMMING the pool but do I need to add cya first? Will it hold the chlorine if the cya is 0?
    Didn't see an answer above to that question. Thanks, Mary
    17x33 inground vinyl pool, 22,000 gallons, 1 1/2 hp hayward pump, Hayward systemII DE filter with chlorinator, north central pennsylvania, heater

  2. Back To Top    #2
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Should I SLAM?

    If the CYA is very low, you will lose a lot of FC to the sun very quickly.
    It is usually best to add CYA up to around 30ppm and then SLAM based on that level. After a week, verify the CYA level.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  3. Back To Top    #3
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Should I SLAM?

    If the water is clear and the CC goes away as soon as you add chlorine then you may not need to SLAM.

    While CYA is zero, until 24 hours after you add CYA, add 2 ppm of chlorine each evening after sunset. That will allow the chlorine to work overnight, instead of being lost to sunlight.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  4. Back To Top    #4

    Re: Should I SLAM?

    Still figuring out this site so I may have already posted this but how do I figure out 2ppm of chlorine to add? And why until 24 hrs after adding cya?
    17x33 inground vinyl pool, 22,000 gallons, 1 1/2 hp hayward pump, Hayward systemII DE filter with chlorinator, north central pennsylvania, heater

  5. Back To Top    #5
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,965

    Re: Should I SLAM?

    Click on the PoolMath link up towards the top of the page. If you need help figuring how to use the calculator let us know. Question - Your CYA at the end of last season? The fact it's 0 now could be suspect...
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  6. Back To Top    #6

    Re: Should I SLAM?

    Added chlorine last night and took some readings this morning. The FC was 1 and the cc was 8!!! Could that be the cya converted to ammonia and thats what the chlorine is breaking up? btw the pool is clear with little to no debris but maybe some pollen. Water is darn cold - 50 - but so is the air. Anyway looks like I will be SLAMMING
    17x33 inground vinyl pool, 22,000 gallons, 1 1/2 hp hayward pump, Hayward systemII DE filter with chlorinator, north central pennsylvania, heater

  7. Back To Top    #7
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Should I SLAM?

    That doess point to ammonia.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  8. Back To Top    #8
    Casey's Avatar
    Join Date
    Apr 2007
    Location
    SW PA
    Posts
    10,157

    Re: Should I SLAM?

    Hold off on CYA for a minute and keep SLAM'ing to get the ammonia down.

    That was a wicked cold winter huh? So glad it's over!!!
    I'd bet you my bikini you'll never get TFP water from a pool store!

    24' Sharkline Venture De Filter

  9. Back To Top    #9

    Re: Should I SLAM?

    Ha that was beyond cold!! and it still is cold! No swimming for a while Is that New England I detect...."wicked" Grew up in Massachusetts myself
    17x33 inground vinyl pool, 22,000 gallons, 1 1/2 hp hayward pump, Hayward systemII DE filter with chlorinator, north central pennsylvania, heater

  10. Back To Top    #10

    Re: Should I SLAM?

    So I added my first loading dose of chlorine to SLAM at 11. fc was 1 and cc 8. Just tested again 2pm and fc now .5 and cc was 12!! Never had a cc that high. Is that the chlorine burning off the presumed ammonia? Why does cya convert over the winter some years and not others? i am so happy to have people to ask these questions. Pool store people are clueless and no one else to ask so all you smart people ...thank you for your time!

    - - - Updated - - -

    ps..cloudy and cool here, am few moments of sun but not much so I don't think sun is eating it up
    17x33 inground vinyl pool, 22,000 gallons, 1 1/2 hp hayward pump, Hayward systemII DE filter with chlorinator, north central pennsylvania, heater

  11. Back To Top    #11
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Should I SLAM?

    No one has completely decoded the mystery of CYA vanishing. As best we can tell it involves some soil bacteria that knows how to break down CYA growing in the water, but even that brief outline isn't proven, let alone figuring out all of the details.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

Posting Permissions

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