Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 4 of 4

Thread: CYA not as high as I thought

  1. Back To Top    #1

    Join Date
    Jun 2013
    Location
    Freehold NJ
    Posts
    133

    CYA not as high as I thought

    I know the CYA "black dot" test can vary greatly between users based upon light, experience, etc. Yesterday was cloudy and I wanted to some chlorine into the pool as I had opened it up two days earlier. I had read the CYA to be about 60. Basing everything on pool school, my schock value should have been 24, and maintance level 7. That called for 11 gallons of 8% bleach. I added 10 because I thought I might be a little off with the CYA. Last night my free chloroine was 28 and thats where it is today. I reran the CYA today in the bright sunshine and came up witha 45. That would put my true shock vaule closer to 19 - 20. So one observation and one question.

    1. All CYA tests are terrible...anything that is that technigue depenend cant be reliable on a daily basis.

    2. My current shock value is about 10 ppm then it should be...will that harm the liner?

    Also, if I ever take my water to Leslies for them to do the CYA test (last year I was out of reagent), they are always way lower then what I get...at least 20 - 30 PPM. My belief that the popularity of SWG is due to the fact that people take use stabilized pucks in feeders, take their water to places like Leslies, who under read the CYA level, the current amount of free chlorine they have isnt high enough to work effectively and half way through the year they get algae....they switch to e SWG and dont have any issues becaus ethe SWG keeps adjusting the amount of free chloroine and does not add CYA to the water....thus all is good....just my 2 cents. Also my leslies never tests for free chlorine, just total...another issue.

    So if anyone can just let me know if I shold be wooried abot my shock value I would appreciatte it.

    Thanks
    38,000 gallon vinyl liner, True "L", Sand Filter, Hayward Heater, Diving Board

  2. Back To Top    #2
    Mod Squad woodyp's Avatar
    Join Date
    Apr 2010
    Location
    East Texas
    Posts
    9,000

    Re: CYA not as high as I thought

    Having your SLAM level of FC a few points above what is recommended ain't gonna hurt anything. The more you use the test, the better you'll get. Pour it back and forth a couple times and compare.
    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!

  3. Back To Top    #3
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,998

    Re: CYA not as high as I thought

    Here are some handy pics of what it should look like, https://www.taylortechnologies.com/C...P?ContentID=44
    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

  4. Back To Top    #4

    Join Date
    Jun 2013
    Location
    Freehold NJ
    Posts
    133

    Re: CYA not as high as I thought

    Thanks guys...I poured it back and forth at least 5 times yesterday and the day before but it was overcast....kept coming in around 60 - 70...today in bright sunshine over my back 45....I was going to start low with the bleach and work up to it, but last year I had an issue withe the total chlorine being higher then free...and if you dont hit that at the right amont you just waisting bleach....sort of got the two issues mixed up...live and learn...
    38,000 gallon vinyl liner, True "L", Sand Filter, Hayward Heater, Diving Board

Posting Permissions

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