Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 2 of 2

Thread: Total Alkalinity only goes to yellow

  1. Back To Top    #1

    Join Date
    Sep 2015
    La Porte, Texas

    Total Alkalinity only goes to yellow

    Using Leslies kit goes to green, but titrates only to yellow (50 drops)
    does that mean TA is really low or very high and I did not hit final titration point?

    FC was 10+ could it be just bleaching the result?
    17' x 35' x 8' in ground Vinyl lined, 24400 gal, age unknown
    Hayward Pro series Side Valve sand filter 3.0ft 62 gpm
    Hayward Super II Pump
    Inline Chlorine feeder (but will primarily use liquid bleach)

  2. Back To Top    #2

    Join Date
    Mar 2007
    San Rafael, CA USA

    Re: Total Alkalinity only goes to yellow

    Yes, at high FC the TA test goes from blue to yellow instead of from green to red. You can add more sodium thiosulfate drops (R-0007) to the initial water sample to neutralize the chlorine. If you can see the transition in color, the test is still valid.

    The TA indicator dye is a mixture of bromocresol green that goes from blue to yellow and methyl red that goes from yellow to red. So when both dyes are active you go from blue+yellow=green to yellow+red=red. High FC levels react with the methyl red dye leaving only the bromocresol green dye that goes from blue to yellow.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

Posting Permissions

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