Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 6 of 6

Thread: Question about the R-003 reagent and the FAS-DPD Chlorine test

  1. Back To Top    #1

    Join Date
    Apr 2014
    Location
    Jamison PA
    Posts
    14

    Question about the R-003 reagent and the FAS-DPD Chlorine test

    Ok, perhaps a completely silly question, but I had an interesting situation yesterday when doing my chlorine water testing. I use a TF-100 test kit. I was performing the FAS-DPD chlorine test, when I got distracted after adding the 5 drops of the R-003 reagent (having a newborn will do that to you!). So after I tended to my son (briefly- less than 5 minutes) I came back to a pink sample! It took 1 drop to clear. I can say it took awhile to get pink it was definitely clear after I added the drops and clear while I was washing my hands before getting the boy. My test kit is new (just a new pool owner this year), and the rest of my numbers were as follows:

    FC 12
    PH 7.5
    TA 70
    CH 225
    CYA 60
    Salt 3800

    I know my FC level is a bit high given the CYA level- I turned down the SWG right after getting the sample. I can't imagine there much in the way of CC's actually in the pool.

    So, is my CC level actually .5, or is there something with leaving the reagent in the sample for awhile that just eventually turns it back pink?

    Usually I don't wait more than 10-15 seconds before dumping the sample if it shows no color change. Should I be waiting longer? Am I being too darn anal retentive over possible .5 CC ?

    Thanks again for your help and everyone's contributions to the website! It's been really useful reading everything, and I've gone my first summer with no algae blooms and the cost of about 1/2 a gallon of MA.
    Last edited by mdomingo; 09-02-2014 at 10:04 AM. Reason: spell check
    Mike, Bucks County PA
    13,500 gallon fiberglass Viking "Triton" pool installed 2013, 1.5 HP Pentair Whisperflo single-speed pump
    Pentair cartridge filter, Pentair IC20 SWG, iRobot Mirra 430 robot
    TF-100 + Speedstir - and so glad I found this site before I started!

  2. Back To Top    #2
    Mod Squad JVTrain's Avatar
    Join Date
    Feb 2014
    Location
    Central Minnesota
    Posts
    5,079

    Re: Question about the R-003 reagent and the FAS-DPD Chlorine test

    That will always happen if you just let it sit with the reagent. Test is meant to be completed quickly for this reason. Your CC is 0.
    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

  3. Back To Top    #3

    Join Date
    Apr 2014
    Location
    Jamison PA
    Posts
    14

    Re: Question about the R-003 reagent and the FAS-DPD Chlorine test

    Awesome! Thank you!
    Mike, Bucks County PA
    13,500 gallon fiberglass Viking "Triton" pool installed 2013, 1.5 HP Pentair Whisperflo single-speed pump
    Pentair cartridge filter, Pentair IC20 SWG, iRobot Mirra 430 robot
    TF-100 + Speedstir - and so glad I found this site before I started!

  4. Back To Top    #4

    Join Date
    Oct 2013
    Location
    Chapin, SC
    Posts
    1,141

    Re: Question about the R-003 reagent and the FAS-DPD Chlorine test

    Yes, it should turn pink almost immediately when you add the r-0003. Then after you add whatever drops of r-0871 it takes to turn it clear, don't wait to empty the test vial or it will turn pink again.
    Pool size: 24000gal inground Vinyl-Taylor k-2006 and k-1766 test kits and-speed stir
    Intermatic P1353ME digital timer w/freeze sensor
    CircuPool Si-45 SWCG System
    Polaris 280 vacuum/Polaris PB4-60 boost pump
    Pentair IntelliFlo VS 3hp Pump--Pentair sand filter

  5. Back To Top    #5

    Re: Question about the R-003 reagent and the FAS-DPD Chlorine test

    R-0003 contains iodide, which can be oxidized to iodine by oxygen in the air. The iodine reacts with reagent R-0870 to give the pink color.

  6. Back To Top    #6
    Wildcat's Avatar
    Join Date
    Jun 2013
    Location
    Tucson, AZ
    Posts
    308

    Re: Question about the R-003 reagent and the FAS-DPD Chlorine test

    When I do the CC test it clouds a little but doesn't turn pink. If I add a drop of R871 it turns clear. Zero CC or .5 CC?
    10000 Gal, IG Pebbletec, pop up cleaners,Hayward EcoStar VS, 425 sq ft Hayward Cartridge, waterfall feature

Posting Permissions

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