Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 10 of 10

Thread: Need advice on what to add as I slowly reduce my CYA

  1. Back To Top    #1
    another one's Avatar
    Join Date
    Jul 2010
    Location
    Seattle area, WA
    Posts
    49

    Need advice on what to add as I slowly reduce my CYA

    Ok, so for the past 4 weeks I've been draining water to reduce my CYA (indoor pool, and I've been listening to the pool store guys and letting them do my testing).

    when I started draining my levels were (from my TF-100):

    pH - 7.5
    FC - 16.5
    CC - 0.5
    TA - 175
    CH - 300
    CYA - 60

    I'm draining around 700 gallons per day (missed a few days), and so far I've drained 14,000 gallons, which according to my spreadsheet means the pool has 40% new water, and 60% old water.

    My levels today are:

    pH - 7.8
    FC - 2.5
    CC - 0
    TA - 65
    CH - 150
    CYA - 35

    My CH has fallen by 50%, TA by 65%, and CYA by 40%. Along the way, the only things I've added is 9 lbs of calcium chloride to get the CH up and 1 quart of 31% muriatic acid to help lower the TA.

    So when I add bleach today to get the FC up to 4, should I try to adjust anything else? By my calculations, I still need to drain about 10,000 more gallons to get the CYA down to 25 which will take about 2 more weeks.

    PS - pool calc says I should add 33 lbs of CaCl to bring CH up to 250, real question is should this be done now or in two weeks.
    29,000 gallon, 18' x 44' Indoor plaster pool - 8'x'8 spa in corner. Well water, TF-100,
    pool cover, Pentair MasterTemp 400k btu heater, Jandy RS-4, 4 x 105 sq ft cartridge filters,
    Wisperflow WFE-4 1.0 HP pump for pool, WFE-6 1.5 HP pump for spa jets, MagnaSweep.

  2. Back To Top    #2

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,084

    Re: Need advice on what to add as I slowly reduce my CYA

    The pH could be lowered if you like. It's in the normal range but the top end of normal. Other than that, everything looks fine. How does your water look?
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  3. Back To Top    #3
    another one's Avatar
    Join Date
    Jul 2010
    Location
    Seattle area, WA
    Posts
    49

    Re: Need advice on what to add as I slowly reduce my CYA

    Water is perfect, my wife commented last night on how there was no chlorine smell whatsoever.

    I think the pH is up because we've been using the spa, the well water pH is around 7.5.
    29,000 gallon, 18' x 44' Indoor plaster pool - 8'x'8 spa in corner. Well water, TF-100,
    pool cover, Pentair MasterTemp 400k btu heater, Jandy RS-4, 4 x 105 sq ft cartridge filters,
    Wisperflow WFE-4 1.0 HP pump for pool, WFE-6 1.5 HP pump for spa jets, MagnaSweep.

  4. Back To Top    #4
    another one's Avatar
    Join Date
    Jul 2010
    Location
    Seattle area, WA
    Posts
    49

    Re: Need advice on what to add as I slowly reduce my CYA

    Last question:

    I plugged in the desired pH level into the pool calc and with FC 4, pH 7.5, TA 60, CH 150 and CYA 35, the CSI is -0.46 which says "Potential to become corrosive to plaster". Do I have to correct this by raising CH?
    29,000 gallon, 18' x 44' Indoor plaster pool - 8'x'8 spa in corner. Well water, TF-100,
    pool cover, Pentair MasterTemp 400k btu heater, Jandy RS-4, 4 x 105 sq ft cartridge filters,
    Wisperflow WFE-4 1.0 HP pump for pool, WFE-6 1.5 HP pump for spa jets, MagnaSweep.

  5. Back To Top    #5
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,347

    Re: Need advice on what to add as I slowly reduce my CYA

    In a plaster pool your CH needs to be higher anyway so that's the correct thing to adjust. I'd bring it up to the recommended range listed in the Pool Calc.
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/¼hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  6. Back To Top    #6
    another one's Avatar
    Join Date
    Jul 2010
    Location
    Seattle area, WA
    Posts
    49

    Re: Need advice on what to add as I slowly reduce my CYA

    Thanks, I'll bring it up to 200+. I'm trying not to add too much that I'm going to drain away anyway over the next 2 weeks, but now that we have a working heater, and it's going to be 90 degrees for the next 4 days, we'll be using the pool a lot.
    29,000 gallon, 18' x 44' Indoor plaster pool - 8'x'8 spa in corner. Well water, TF-100,
    pool cover, Pentair MasterTemp 400k btu heater, Jandy RS-4, 4 x 105 sq ft cartridge filters,
    Wisperflow WFE-4 1.0 HP pump for pool, WFE-6 1.5 HP pump for spa jets, MagnaSweep.

  7. Back To Top    #7
    Melt In The Sun's Avatar
    Join Date
    Oct 2009
    Location
    Tucson, AZ
    Posts
    3,899

    Re: Need advice on what to add as I slowly reduce my CYA

    Are you done replacing water? I would wait to add the calcium til you are. I don't think -.46 isn't low enough to cause damage over that short amount of time.
    11,200 gal, Pebble-Tec; Tristar 2-speed 1hp - Swimclear 325 ft2 cart - SWG - A & A in-floor cleaner - Heat pump. For the poolside cooking, a Yoder Wichita and a Big Steel Keg!
    TF Test Kits -- PoolMath -- Pool School
    Make each day your masterpiece. - John Wooden

  8. Back To Top    #8
    another one's Avatar
    Join Date
    Jul 2010
    Location
    Seattle area, WA
    Posts
    49

    Re: Need advice on what to add as I slowly reduce my CYA

    Not done replacing yet, two more weeks at 700 gallons per day. My well pump runs as much as my pool pump.
    29,000 gallon, 18' x 44' Indoor plaster pool - 8'x'8 spa in corner. Well water, TF-100,
    pool cover, Pentair MasterTemp 400k btu heater, Jandy RS-4, 4 x 105 sq ft cartridge filters,
    Wisperflow WFE-4 1.0 HP pump for pool, WFE-6 1.5 HP pump for spa jets, MagnaSweep.

  9. Back To Top    #9
    Isaac-1's Avatar
    Join Date
    May 2010
    Location
    SW Louisiana
    Posts
    6,711

    Re: Need advice on what to add as I slowly reduce my CYA

    What CYA level are you shooting for? I maintain my indoor pool at a CYA level of 20 ppm, just because the advice around here is some CYA is good, and the common test only read down to 20ppm.

    Ike
    Indoor 20x40 35,000 gallon vinyl pool with 1.5 HP 2 speed Jandy FloPro pump, Hayward EC75 Perflex DE filter, 11 4x12 Techno-Solis solar panels w/ Aquasolar controller, Aquabot Turbo T Robot Cleaner. Also LMI metering chlorine dispenser pump and HotSpring Jetsetter
    I use and endorse TFtestKits TF-100 from http://tftestkits.net
    ~Remember TFP counts on your donations to keep this site ad free~

  10. Back To Top    #10
    another one's Avatar
    Join Date
    Jul 2010
    Location
    Seattle area, WA
    Posts
    49

    Re: Need advice on what to add as I slowly reduce my CYA

    I'm shooting for a CYA of 25 for now, this winter, if we stop using the pool for a while, I'll drain some more water and try to get it down to 20 which seems to be the recommended level.
    29,000 gallon, 18' x 44' Indoor plaster pool - 8'x'8 spa in corner. Well water, TF-100,
    pool cover, Pentair MasterTemp 400k btu heater, Jandy RS-4, 4 x 105 sq ft cartridge filters,
    Wisperflow WFE-4 1.0 HP pump for pool, WFE-6 1.5 HP pump for spa jets, MagnaSweep.

Posting Permissions

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