Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 12 of 12

Thread: DPD test

  1. Back To Top    #1

    Join Date
    Jun 2015
    Location
    Phx Az
    Posts
    13

    DPD test

    I have a Taylor k-2005 kit (along with the FAS-DPD) When using the DPD FC test it consistently shows much lower FC than the FAS-DPD test. This morning for example the FAS-DPD test read 12ppm FC. Using the DPD test with the X2 dilution it only read about 6ppm. Am i doing something wrong?

  2. Back To Top    #2

    Join Date
    Sep 2013
    Location
    Connecticut
    Posts
    728

    Re: DPD test

    Sorry to ask the obvious, but did you multiply your DPD test result by two, to account for the dilution?
    18' x 48" ring top pool (Summer Escapes); 5500 gallons; set up June - October, stored during winter; Intex 2500 gph pump (B size cartridge filter) Hayward 21" sand filter + 1.5 hp single speed Powerflo Matrix pump (upgrade October 2016) *** K-2006 test kit, refills from tftestkits

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

    Re: DPD test

    My question as well...

    Also, DPD can bleach out at high FC levels, making it read artificially low. The OTO (yellow) test never bleaches out, it just gets darker and darker.
    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
    Jun 2015
    Location
    Phx Az
    Posts
    13

    Re: DPD test

    Yes i multiplied by 2 to make up for the dilution.

  5. Back To Top    #5

    Join Date
    Aug 2014
    Location
    Shallotte, NC
    Posts
    693

    Re: DPD test

    Quote Originally Posted by particleman View Post
    Yes i multiplied by 2 to make up for the dilution.
    This is hard to follow. What were you CC readings?

  6. Back To Top    #6

    Join Date
    Jun 2015
    Location
    Phx Az
    Posts
    13

    Re: DPD test

    My CC is 0 according to the fas-dpd test.
    FC 12.5
    CC 0
    TA 70
    PH 7.5
    CYA 45-50

  7. Back To Top    #7

    Join Date
    Aug 2014
    Location
    Shallotte, NC
    Posts
    693

    Re: DPD test

    I'm going to make a big guess and say you may have old reagents. Both R-0002 and R-0003 should be colorless. If they are tinted yellow, toss them (and the results) out.

    Personally, I'd listen to the FAS-DPD, if you have fresh reagents and are following the instructions to a "T."

  8. Back To Top    #8

    Join Date
    Jun 2015
    Location
    Phx Az
    Posts
    13

    Re: DPD test

    Yep bad reagents just got back from the pool store bought new R0001 and R0002 and all is good. Thank you

  9. Back To Top    #9
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: DPD test

    Why didn't you just trust the FAS-DPD? The DPD is the worst of the 3 chlorine tests IMO.
    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!

  10. Back To Top    #10

    Join Date
    Jun 2015
    Location
    Phx Az
    Posts
    13

    Re: DPD test

    I just didn't want to use the FAS test every day. The best part was that the guy at leslie's gave me both bottles for $5 and said happy 4th of July. So im kinda glad I went. I do have one last question though. According to the pool math my FC should be 4-8ppm is it bad that I take it to 12ppm at night? I lose 4ppm on average during the day so by night time im down to 8ppm.

  11. Back To Top    #11
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: DPD test

    That is overkill. You just want to keep it above 4ppm. Target 9 or so. The higher you go, the more you will lose.
    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!

  12. Back To Top    #12

    Join Date
    Jun 2015
    Location
    Phx Az
    Posts
    13

    Re: DPD test

    Alright I will do that. Thanks for all your help

Posting Permissions

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