Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 13 of 13

Thread: To Shock or not to Shock

  1. Back To Top    #1

    Join Date
    Aug 2015
    Location
    Grants Pass, OR
    Posts
    17

    To Shock or not to Shock

    Hello,

    Roguewave, here. 10 year lurker, first time poster. There is no doubt in my mind that this is the best place on the web for pool care advice and I appreciate all I've learned from many of you over the years.

    Forgive the long post, but consider some of it my introduction.

    The basics:

    20,000 gallon, 16x32 vinyl lined, in-ground, diving pool.

    9 Fafco panels and a Compool controller. Our pool season generally runs April 1st through the end of October and we're in it almost every day we're home.

    Taylor K2006C

    Currently using trichlor pucks until CYA rises to where I want it for a given season and then bleach.

    This morning's parameters:

    CYA - 60
    Cl - 5.5
    pH - 7.5
    Al - 90 (added 38 oz of baking soda this morning)
    CA - 80 (here at TFP I learned not to concern myself much with CA for this vinyl pool)
    CC < 0.5

    Haven't had to shock to lower CC yet this year. The cover is normally off all day, which probably helps (according to this site.)

    On the advice of the pool installer, I installed an ecomatic SWG when the pool was new about 10 years ago. Well... the cell had a long life, but finally gave up the ghost a couple of years ago. Now since ecomatic has gone the way of the Dodo, I looked into aftermarket cells and the reviews of their quality were pretty awful.

    So... without the budget to replace the ecomatic entirely, I was forced to switch to the old standard approach.

    I keep my parameters tight. Alkalinity never gets beyond 90 or 110. pH almost never off by more than 0.1, Keep chlorine about 1 ppm above the minimum recommendation as per The Pool Calculator. Haven't had any algae blooms in what seems like forever.

    We have a week-long, family trip planned in the next month and, rather than run the pump, I plan to leave the cover on and bump up the chlorine with enough liquid bleach to hold 'er 'til we get back (erring on the side of caution, of course.)

    I estimate the minimum to be about 4 bottles of 8% (or 7?) Walmart concentrate. So I would probably do 6. With the cover on and a CYA of 60, I believe it's likely we will be coming home to a pool that will need a few days with the cover off.

    According to chem geek's chart, I estimate I need about 10 bottles, total, to shock.

    Using the K2006C, I get < 0.5 CC when using a 10 ml sample. The reagent does turn it a hair pink and one drop returns it to clear. But the funny thing is, when I use the 25 ml mark, I can't get the sample to return to pink no matter how much reagent I use.

    This is puzzling, but I feel it's OK to figure that I don't have much CC.

    So... my question is...

    Would it be worth it to go ahead and shock... figuring that I would probably have to add some thiosulfate upon our return?

    Or would just a moderately elevated level of chlorine finish oxidizing what little CC I have?

    Or?

  2. Back To Top    #2
    Texas Splash's Avatar
    Join Date
    Jun 2014
    Location
    South-Central Texas, Marion/San Antonio
    Posts
    12,968

    Re: To SLAM or not to SLAM

    If I'm reading all of this correctly, your big issue is that you're prepping for vacation and don't want the FC to drop too much while you're away correct? If that's true, why not wait on the pucks. Use the bleach now. Take it to SLAM/Shock level with bleach again just before you leave, put the pucks in at that time, then cover. Or am I missing part of the equation.
    Pat (a.k.a. Texas Splash) ~ My Pool: Viking Fiberglass; 17,888 Gal; Waterway Supreme 2-sp/2-hp pump; Hayward Ctg filter; TF-100 w/ Speed Stir
    Vital Links: POOL SCHOOL, RECOMMENDED LEVELS, RECOMMENDED CHEMICALS, Poolmath Calculator, SLAM, Chlorine/CYA CHART.
    If you enjoyed your TFP experience, please consider donating to Support TFP!

  3. Back To Top    #3
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: To SLAM or not to SLAM

    If you go to shock level and cover the pool, odds are you will return to a clear pool that still has some FC remaining.

    Since it's safe to swim up to shock level, and there's no way the FC level will climb during the time you are away, you shouldn't need thiosulphate at all. All you need to do upon return is test the pH, FC, and CC. If FC is less than 10, the pH reading is reliable. If FC is above 10, leave the cover off and wait a day. If CC is above .5, wait a day. If it's still there, SLAM it.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  4. Back To Top    #4

    Join Date
    Aug 2015
    Location
    Grants Pass, OR
    Posts
    17

    Re: To Shock or not to Shock

    Quote Originally Posted by Richard320 View Post
    ...Since it's safe to swim up to shock level...
    Looks like the answer came in an unexpected form. Another day at TFP, another lesson learned.

    Shock it is!

    Thanks!

    P.S. Subject heading edited for accuracy

  5. Back To Top    #5
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,998

    Re: To Shock or not to Shock

    Welcome to TFP.

    What country is Jefferson state in? Location and climate is an important factor when we help you with your pool. Please update your location and add your pool info to your signature, more here, Pool School - Getting Started
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  6. Back To Top    #6
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: To Shock or not to Shock

    Quote Originally Posted by pooldv View Post
    Welcome to TFP.

    What country is Jefferson state in? Location and climate is an important factor when we help you with your pool. Please update your location and add your pool info to your signature, more here, Pool School - Getting Started
    It's okay. I know where it is. Far Northern California
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  7. Back To Top    #7
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,998

    Re: To Shock or not to Shock

    Quote Originally Posted by Richard320 View Post
    It's okay. I know where it is. Far Northern California
    What? CA is its own country now with states? LOL
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  8. Back To Top    #8

    Join Date
    Aug 2015
    Location
    Grants Pass, OR
    Posts
    17

    Re: To Shock or not to Shock

    Quote Originally Posted by Richard320 View Post
    It's okay. I know where it is. Far Northern California
    Yes... and Southern Oregon. Climate is all pretty much the same in the Great State of Jefferson. Zone 7. Decent springs and falls. Hot, dry summers and cold, wet winters.

    Our benevolent overlord, Big Brother Google, knows all...

    https://www.google.com/#q=jefferson+state
    20,000 gallon, 16x32 vinyl lined, in-ground, diving pool.
    Fafco panels & Compool controller. Pool season +/- 4/1-10/31
    Trichlor pucks until CYA rises to where I want it for a given season, then liquid bleach.
    Sand Filter
    Taylor K2006C

  9. Back To Top    #9
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: To Shock or not to Shock

    Quote Originally Posted by Roguewave View Post
    Yes... and Southern Oregon. Climate is all pretty much the same in the Great State of Jefferson. Zone 7. Decent springs and falls. Hot, dry summers and cold, wet winters.

    Our benevolent overlord, Big Brother Google, knows all...

    https://www.google.com/#q=jefferson+state
    I didn't need google. I know a lot of California history and geography as a transplanted Northern Californian.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  10. Back To Top    #10

    Join Date
    Aug 2015
    Location
    Grants Pass, OR
    Posts
    17

    Re: To Shock or not to Shock

    Quote Originally Posted by Richard320 View Post
    I didn't need google. I know a lot of California history and geography as a transplanted Northern Californian.
    Sorry. That was intended more for pooldv or anyone interested.

    Much like Central/Northern Cal would like to break off from Southern Cal... the far north of California would like to break away ALMOST as much as many Southern Oregonians would like to break away from Portland down through Eugene. And if it weren't for WWII... it just might have happened.

    But we digress...

    Good thing you answered the primary question for this thread already... 'cuz we're gettin' a little off topic.
    20,000 gallon, 16x32 vinyl lined, in-ground, diving pool.
    Fafco panels & Compool controller. Pool season +/- 4/1-10/31
    Trichlor pucks until CYA rises to where I want it for a given season, then liquid bleach.
    Sand Filter
    Taylor K2006C

  11. Back To Top    #11
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,998

    Re: To Shock or not to Shock

    LOL! That is true, but trying to read and respond to hundreds of threads per day doesn't leave a lot of time to stop to google locations. Although, I am curious about what Jefferson State is, so I might go google that just for fun. Northern CA would be pretty helpful.
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  12. Back To Top    #12

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,084

    Re: To Shock or not to Shock

    +1 what pooldv said. If OP had posted a question on closing (or opening) Jefferson State would have told me nothing about his climate and I would have simply gone on to something else.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  13. Back To Top    #13

    Join Date
    Aug 2015
    Location
    Grants Pass, OR
    Posts
    17

    Re: To Shock or not to Shock

    Well fortunately I didn't ask a question that really hinged on climate this time, but... I can see how important this is.

    Profile updated.

    Thanks again for the help. Bought more liquid bleach today.

    Have a nice evening
    20,000 gallon, 16x32 vinyl lined, in-ground, diving pool.
    Fafco panels & Compool controller. Pool season +/- 4/1-10/31
    Trichlor pucks until CYA rises to where I want it for a given season, then liquid bleach.
    Sand Filter
    Taylor K2006C

Posting Permissions

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