Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 5 of 5

Thread: Hydrogen peroxide to lower FC.

  1. Back To Top    #1

    AUSpool's Avatar
    Join Date
    Sep 2015
    Location
    Sunshine Coast, Australia.
    Posts
    351

    Hydrogen peroxide to lower FC.

    I have 2 pools that had high FC, and recalled reading about hydrogen peroxide to reduce FC. Normally I would just turn off the chlorinator and let the FC come down naturally but the water is cold, there's not much sun around and I found some cheap hydrogen peroxide by chance and thought I would share my results.

    From a quick search I found this quote;
    "27% hydrogen peroxide at a reasonable price of $17 per gallon. It would only take 115 fluid ounces (around 3-1/2 quarts so somewhat less than one gallon) to lower the chlorine by 50 ppm in 10,000 gallons."

    With that as a starting point and using Google to convert to metric and then adjusting for my pool I get; 1,040ml of 27% H2O2 in 29,000L to lower FC by 20ppm.

    As luck had it I found 5 litres of 190g/L or 19%w/v hydrogen peroxide for $10, a cancelled order. Adjusting for 19% I get; 1,540ml of 19% H2O2 in 29,000L to lower FC by 20ppm.

    I don't know where I went wrong but my observed results are out by a factor of 2.
    Day 1: FC = 25. + 1,500ml 19%H2O2 + 1.5hrs Cl2 run time + 24hrs. FC = 15.
    Day 2: FC = 15. + 1,500ml 19%H2O2 + 1.5hrs Cl2 run time + 24hrs. FC = 5.

    In reality it was 1.5L of 19% H2O2 in 29,000L to lower FC by 10ppm.
    Or, 530ml of 19% H2O2 in 10,000L to lower FC by 10ppm.
    Or 68 fluid ounces of 19% H2O2 in 10,000 gallons to lower FC by 10ppm.
    Steve.
    30,000L (8,000g) Pebblecrete | Davey 3sp Eco pump | Poolrite sand filter & SWCG |
    Waterco solar panels & Astral E140 pump| K2006, CCL reagents, BlueDevil pH, Salt meter & K1766 | Town water - pH 7.2, TA 50, CH 60 | Esky full of coldies |

  2. Back To Top    #2
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,601

    Re: Hydrogen peroxide to lower FC.

    The quick and dirty rule of thumb is this - the amount in oz of 6% bleach it takes to raise your FC by X ppm's is equal to the amount of 3% H2O2 needed to lower the FC by X ppm's. That rule of thumb is good to use because it's a lot easier to find 3% peroxide in a drug store and most people use peroxide as an FC lowering chemical in spas where the water volumes are A LOT lower.
    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  3. Back To Top    #3

    Join Date
    Aug 2015
    Location
    novato/CA
    Posts
    37

    Re: Hydrogen peroxide to lower FC.

    I used yellow gone a couple of time to lower my FC when I got my SWG and was testing the setting. use it wisely though because it will eat up all your FC pretty quickly if you put too much of it in your pool. it will also lower your PH in the process.
    Fiberglass 5.5K gal - Pentair Superflo VS - Circupool RJ 30+ - Star Rite PLM 200 -

  4. Back To Top    #4
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,601

    Re: Hydrogen peroxide to lower FC.

    Quote Originally Posted by misteur G View Post
    I used yellow gone a couple of time to lower my FC when I got my SWG and was testing the setting. use it wisely though because it will eat up all your FC pretty quickly if you put too much of it in your pool. it will also lower your PH in the process.
    That's an EDTA/Ammonium Sulfate based chemical. It's meant to work as an algaecide by the in-situ formation of monochloramine which is a powerful algaestat. But it does so by consuming FC in the process. A lot of FC!

    Peroxide is probably the least harmful choice, it simply annihilates itself with chlorine and forms oxygen gas, chloride and excess HCl.
    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  5. Back To Top    #5

    AUSpool's Avatar
    Join Date
    Sep 2015
    Location
    Sunshine Coast, Australia.
    Posts
    351

    Re: Hydrogen peroxide to lower FC.

    Quote Originally Posted by JoyfulNoise View Post
    The quick and dirty rule of thumb is this - the amount in oz of 6% bleach it takes to raise your FC by X ppm's is equal to the amount of 3% H2O2 needed to lower the FC by X ppm's. That rule of thumb is good to use because it's a lot easier to find 3% peroxide in a drug store and most people use peroxide as an FC lowering chemical in spas where the water volumes are A LOT lower.
    Thanks Matt,
    I did see something similar but in honesty didn't really give much thought to either thinking it would be to costly to use any form of peroxide hear. It was by shear chance I found the 'Spa Protector' product for $10, a quick search reviels it normally retails for closer to $50 and for $50 I would have abandoned the idea. For $10 it was a bit an experiment and allowed me to lower the FC in one of my pools before replacing the seals in the filter.
    Steve.
    30,000L (8,000g) Pebblecrete | Davey 3sp Eco pump | Poolrite sand filter & SWCG |
    Waterco solar panels & Astral E140 pump| K2006, CCL reagents, BlueDevil pH, Salt meter & K1766 | Town water - pH 7.2, TA 50, CH 60 | Esky full of coldies |

Posting Permissions

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