Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 3 of 3

Thread: How much ppm should I add CYM to a in ground spa

  1. Back To Top    #1

    Join Date
    Mar 2014
    Arroyo Grande/California

    How much ppm should I add CYM to a in ground spa

    Hi - I just filled my in ground spa with 930 gal of water. I looked at the calculator and all over the forum, but could not find an answer that has a recommendation of how much CYM should be added to a in ground spa when using liquid chlorine. I think 30ppm is correct, but it could be 20ppm or even 50ppm. The directions on the Splash CYM I bought suggested 30ppm, but that could be for a pool.

    Thank you.

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

    Re: How much ppm should I add CYM to a in ground spa

    Is the spa usually covered? If so, then you would not need very high CYA levels and I would suggest about 30ppm. If it is not covered and exposed to the sun, then I might lean closer to 50ppm.

    You can either add the CYA and then just use bleach, or use PoolMath to calculate how much Dichlor would be needed to get to you desired CYA level and then slowly add that over multiple days to maintain FC as well. Once you put the required CYA in the water, then switch to bleach only.
    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
    Mod Squad JVTrain's Avatar
    Join Date
    Feb 2014
    Central Minnesota

    Re: How much ppm should I add CYM to a in ground spa

    This is the thread you're looking for: How do I use Chlorine in my Spa


    On a fresh fill use Dichlor until you get to 20-30 ppm CYA. (10 ppm FC = 9 ppm CYA)
    Then switch to Clorox Unscented 6% bleach.
    Never let FC drop to Zero for any length of time. Keep it between 3-6 ppm normally, min of 1 ppm, and shock to 12 ppm once a week.
    Use MPS if needed before hot tub party's and/or once a week to help oxidation. Don't use more than needed, because it's acidic and may lower your TA/pH.
    Dichlor, Bleach and MPS is all you need to keep your tub sanitized.
    Use PoolMath to calculate exact amounts to add.

    And of course, this just popped into my head. (sorry for the randomness)

    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

Posting Permissions

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