Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 10 of 10

Thread: FC of 15 / CYA of 55

  1. Back To Top    #1

    Join Date
    Mar 2016
    Location
    Tampa, Florida
    Posts
    94

    FC of 15 / CYA of 55

    Just got back from a week long vacation and dying to jump in the pool. But, wanted to confirm mostly for my 3 year old that it is safe to jump in without lowering the FC first. Current readings are:

    FC - 15
    TC - .5
    pH - 7.4
    TA - 70
    CYA - 55
    Gallons 13,860 / IG Pebble / Hayward OmniLogic / Hayward Swim Clear Filter / Hayward EcoStar / Hayward TriStar VS (for water features) / Hayward HeatPro Heat Pump / Date of build 3/11/16 / Other features: Spa / Hayward Colorlogic LED lights (2 in pool / 1 in spa) / Pentair LED Bubblers (2 one on each sun shelf) / Pentair Color Cascade Laminars (4 around pool) / Taylor K-2006 Test Kit

  2. Back To Top    #2
    Mod Squad kimkats's Avatar
    Join Date
    Jul 2012
    Location
    Tallahassee, FL
    Posts
    34,010

    Re: FC of 15 / CYA of 55

    Let him in!! Here is the chart:

    Pool School - Chlorine / CYA Chart

    It is safe to swim if the FC is just under the SLAM level for you CYA. As you can see you are well under it! CANNON BALL!!!!

    Kim
    TFP Moderator 33x52 round AG 25,600 gals Sand Filter 1.5hp Pump - 2 Speed, SLAM, Pool School, Recommended Levels, Recommended Chemicals, Pool Math, Chlorine/CYA Chart, TF-100 Test Kit

  3. Back To Top    #3

    TFP Guide


    Join Date
    Feb 2015
    Location
    Chandler AZ
    Posts
    1,061

    Re: FC of 15 / CYA of 55

    Reference the Chlorine/CYA Chart: Pool School - Chlorine / CYA Chart

    It's safe to swim anytime the FC is between the minimum and shock level listed for your CYA level and you can clearly see the bottom of the entire pool, and your pH is within the recommended range.
    Gene
    ​12,300 gal IG play pool - Pebbletec - built 10/1999 || Hayward S360SX 36" sand filter || Hayward Ecostar SP3400 VSP || A&A In-Floor cleaning system || Quik Water Leveler || Quik Dek-clor (limited use)
    TF-100 testkit / Speedstir - A good test kit is not an expense, it's an investment

  4. Back To Top    #4

    Join Date
    Mar 2016
    Location
    Tampa, Florida
    Posts
    94

    Re: FC of 15 / CYA of 55

    Great - now a followup question. I know that chart says my target FC should be 4 but the other chart here suggests it should be higher (Chlorine/CYA Chart).

    I was thinking of maintaining the target FC at between 8 and 10. I have battled a few mustard algae instances in the last 6 months and question whether I needed to target a FC higher than suggested in the one chart.

  5. Back To Top    #5
    Mod Squad kimkats's Avatar
    Join Date
    Jul 2012
    Location
    Tallahassee, FL
    Posts
    34,010

    Re: FC of 15 / CYA of 55

    Your pool has told you that answer.....yes. Go higher to keep it gone.
    TFP Moderator 33x52 round AG 25,600 gals Sand Filter 1.5hp Pump - 2 Speed, SLAM, Pool School, Recommended Levels, Recommended Chemicals, Pool Math, Chlorine/CYA Chart, TF-100 Test Kit

  6. Back To Top    #6

    Join Date
    Mar 2016
    Location
    Tampa, Florida
    Posts
    94

    Re: FC of 15 / CYA of 55

    ^ good point.

  7. Back To Top    #7

    TFP Guide


    Join Date
    Feb 2015
    Location
    Chandler AZ
    Posts
    1,061

    Re: FC of 15 / CYA of 55

    If your CYA reading falls between the listed numbers on the chart, always round UP to the next number. With your reported CYA of 55, you would use the levels for CYA of 60.

    On the Pool School - Chlorine / CYA Chart - for CYA 60, minimum is FC 5, target is FC 7-9 and shock level FC is 24.

    Keeping it a little higher than target may help keep the mustard algae away a bit better.
    Gene
    ​12,300 gal IG play pool - Pebbletec - built 10/1999 || Hayward S360SX 36" sand filter || Hayward Ecostar SP3400 VSP || A&A In-Floor cleaning system || Quik Water Leveler || Quik Dek-clor (limited use)
    TF-100 testkit / Speedstir - A good test kit is not an expense, it's an investment

  8. Back To Top    #8

    Join Date
    Mar 2016
    Location
    Tampa, Florida
    Posts
    94

    Re: FC of 15 / CYA of 55

    Quote Originally Posted by proavia View Post
    On the Pool School - Chlorine / CYA Chart - for CYA 60, minimum is FC 5, target is FC 7-9 and shock level FC is 24.
    To make sure we are on the same page, I have a SWG and the chart for a SWG doesn't give a range like 7-9 and actually shows target as Much lower. That's why I asked the follow up question, because following what link everyone provided say I would be targeting with a SWG a FC of "4" with a CYA of 60.

    Why the target differences in the charts for SWG and non- SWG pools? Clearly following that SWG chart I am aiming quite low targeting FC of 4 as it says???
    Gallons 13,860 / IG Pebble / Hayward OmniLogic / Hayward Swim Clear Filter / Hayward EcoStar / Hayward TriStar VS (for water features) / Hayward HeatPro Heat Pump / Date of build 3/11/16 / Other features: Spa / Hayward Colorlogic LED lights (2 in pool / 1 in spa) / Pentair LED Bubblers (2 one on each sun shelf) / Pentair Color Cascade Laminars (4 around pool) / Taylor K-2006 Test Kit

  9. Back To Top    #9
    Mod Squad kimkats's Avatar
    Join Date
    Jul 2012
    Location
    Tallahassee, FL
    Posts
    34,010

    Re: FC of 15 / CYA of 55

    SWG pools have FC being added the whole time the pump is running. A non-swg pool only has FC being added once a day for most people so it has to "last" all day/night so will be higher and float down as the sun and stuff uses it up.

    Know any of the levels are "ranges". There is always an outlier and you just might be one. We target the medium and have others adjust as needed. Each pool is different so we do what the pool likes/needs when it shows us what it wants.

    Kim
    TFP Moderator 33x52 round AG 25,600 gals Sand Filter 1.5hp Pump - 2 Speed, SLAM, Pool School, Recommended Levels, Recommended Chemicals, Pool Math, Chlorine/CYA Chart, TF-100 Test Kit

  10. Back To Top    #10

    TFP Guide


    Join Date
    Feb 2015
    Location
    Chandler AZ
    Posts
    1,061

    Re: FC of 15 / CYA of 55

    Oops - sorry, I missed the SWG.

    Kim is spot on in her explanation of why there are different numbers for SWG versus non-SWG chlorination methods. The ranges are a baseline recommendation - cause you have to start somewhere. Personally, I use a slightly higher range for my measured CYA - because it works for me and my pool.
    Gene
    ​12,300 gal IG play pool - Pebbletec - built 10/1999 || Hayward S360SX 36" sand filter || Hayward Ecostar SP3400 VSP || A&A In-Floor cleaning system || Quik Water Leveler || Quik Dek-clor (limited use)
    TF-100 testkit / Speedstir - A good test kit is not an expense, it's an investment

Posting Permissions

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