Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 11 of 11

Thread: Before/after 50% refill, still out of balance

  1. Back To Top    #1

    Join Date
    Mar 2014
    Location
    Mesa, AZ
    Posts
    2

    Before/after 50% refill, still out of balance

    New pool owner here as of last year. I decided to start the TFCP method this season after messing with 4-in-1 chlorine tabs and Shock last year (so far just adding Clorox Bleach from Costco for chlorine) and here are my before/after results using the TF-100 test kit when I replaced 50% of my water:

    Before:
    2014-05-15
    Chlorine: 0
    Free Chlorine:
    Combined Chloramines:
    Total Chlorine (FC+CC):
    pH: 8.2
    Calcium Hardness: 700 ppm
    Total Alkalinity: 180
    CYA: 100

    2014-05-19 drained 50% of pool and refilled

    After:
    2014-05-27
    Chlorine: 3 (just added 121oz Chlorine an hour before testing)
    Free Chlorine: 4 ppm
    Combined Chloramines: 0
    Total Chlorine (FC+CC): 4
    pH: 8.2
    Calcium Hardness: 625 ppm
    Total Alkalinity: 170
    CYA: 70

    So my pH, CH, TA, and CYA came closer in line, but are still out of whack. My main concern is having my chlorine levels burn off in three to four days which leads to the beginning stages of algae forming on one end of the pool wall.

    With AZ water being so hard, how can I get my CH, TA, and CYA lower? The Pool Calculator still tells me I should replace 58% of my water to come in line with CH and replace 43% to lower CYA. I know I need to lower CYA and pH to allow the chlorine to last longer, but I'm not too keen on replacing 50% of the water for the second time in a single month. Thanks for your guidance.
    25K gal, sand, IG, plaster, Dolphin Supreme M5 cleaning robot

  2. Back To Top    #2

    Join Date
    Apr 2014
    Location
    Hackettstown, NJ
    Posts
    35

    Re: Before/after 50% refill, still out of balance

    First off you mention AZ water being so hard, can you quantify that? run the FC, CC, PH, CH, and TA tests on your fill water? post those results and I'm sure someone around here can help you with your balance. your PH and TA can be lowered using Muriatic Acid, and pool Calculator / pool math will tell you how much. CH you will only be able to lower to the value you get from your fill water, unless you start harvesting rainwater (CH=0) and I don't know how rare that may be in Mesa.
    25.5K gal vinyl IGP 3.5' - 8' depth. 1.5HP single speed A.O. Smith C48L2N134B1 motor on a Hayward SP2610X15 Pump. 40 ft2 D.E. Filter Hayward model EC75A. Hayward Chlorinator model CL200. single skimmer, 2 Returns. TF100 Test Kit/Speed Stir.

  3. Back To Top    #3
    UN1017's Avatar
    Join Date
    May 2012
    Location
    Sacramento, CA
    Posts
    288

    Re: Before/after 50% refill, still out of balance

    Quote Originally Posted by tlbig10 View Post
    With AZ water being so hard, how can I get my CH, TA, and CYA lower? The Pool Calculator still tells me I should replace 58% of my water to come in line with CH and replace 43% to lower CYA. I know I need to lower CYA and pH to allow the chlorine to last longer, but I'm not too keen on replacing 50% of the water for the second time in a single month. Thanks for your guidance.

    So my pH, CH, TA, and CYA came closer in line, but are still out of whack. My main concern is having my chlorine levels burn off in three to four days which leads to the beginning stages of algae forming on one end of the pool wall.
    Welcome to TFP.

    You have already taken many of the steps needed to adjust the levels which you are concerned about. You brought your CYA down to 70, which is a little high, but in AZ it might be ok.

    Unfortunately, as Dhoover85 was touching on, your fill water CH (and TA too) is likely above recommended levels. Short of you trucking in water with a lower CH, you will need to manage it the best you can.

    That takes us to the last point, your TA is high but you will need to follow these steps by reducing pH and aerating, in order to lower it.

    Quote Originally Posted by tlbig10 View Post
    So my pH, CH, TA, and CYA came closer in line, but are still out of whack. My main concern is having my chlorine levels burn off in three to four days which leads to the beginning stages of algae forming on one end of the pool wall.
    Chlorine levels are not meant to last three to four days. You need to dose daily (maybe every other day if you're lucky). Extreme sun exposure makes it very challenging.

    You need to focus on your FC and CYA. Keeping an effective level of FC will keep that algae in check. Monitor/adjust your pH daily and your TA should fall in line on its own.
    15'x30' IG - Roman-style - 14K - Pebble Fina Classico
    Filter: Jandy CL460 Pump: Jandy Stealth SHPF1.5 SWG: Jandy AquaPure 1400 Cleaner: Jandy RayVac Test Kit: TF-100 w/SpeedStir

    Chlorine/CYA Chart----Extended Test Kit Directions----SLAM

  4. Back To Top    #4
    BoDarville's Avatar
    Join Date
    Jun 2012
    Location
    DFW, Texas
    Posts
    3,840

    Re: Before/after 50% refill, still out of balance

    The reason that the CYA did not drop as much as you were expecting is that the actual CYA level was very likely higher than your initial reading of "100". This is because the maximum reading on the CYA view tube is 100. Whenever a CYA results comes back at 90 or more, we recommend retesting using the procedure described in post # 8 on this page: Extended Test Kit Directions.
    Since your current CYA is at 70, you do not need to worry about this now...just posting for future reference and for the benefit of others reading this thread.

    Likewise, the CH did not drop at a rate corresponding to the % of water that was replaced due to the hardness of AZ water. I have read that there are reverse-osmosis treatments that can reduce CH and that this service is most popular in AZ and SoCal relative to other parts of the country.
    Gold Supporter, TFP Lifetime Supporter, 26,680 gal Plaster IGP 3.5 - 10' depth / Attached Waterfall Spa, Manually Chlorinated, Triton Sand Filter, 1.5 HP * 1.1 SF = 1.65 SFHP 1-speed Pentair WhisperFlo WF-26 Pump, 400K BTU NG Teledyne Laars Series One Heater, Polaris 360, Test Kit Comparison, Chlorine/CYA Chart, SLAMing Your Pool, OCLT
    A good test kit is an investment, not an expense.

  5. Back To Top    #5

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,085

    Re: Before/after 50% refill, still out of balance

    Welcome to the forum.
    The Pool Calculator still tells me I should replace 58% of my water to come in line with CH and replace 43% to lower CYA. I know I need to lower CYA and pH to allow the chlorine to last longer, but I'm not too keen on replacing 50% of the water for the second time in a single month.
    You have numbers you can live with but they are marginal. Leave your numbers right where they are if that's what you want.

    The important thing to understand about TFP is learning how to deal with what you do. If you choose to keep your CH high (and it will go higher) then learn what you do to compensate for that. If you choose to keep your CYA @ 70 ppm, learn what steps you take to keep normal levels.

    You are not far out of "normal ranges but the kit and pool math is telling you you are borderline and need to compensate for it.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  6. Back To Top    #6
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,965

    Re: Before/after 50% refill, still out of balance

    In preparation for a possible future repeat drain/refill, I agree with the suggestion of testing the fill water and posting the results.

    If you don't want to do it right now, get your PH down to 7.2 ASAP to avoid the high CH/PH/TA from causing scale. Use PoolMath and muratic acid.

    I've run with a CYA of 70, and it's doable if you diligently test your FC and PH daily and keep those 2 in range - you can manage for awhile if another drain/refill is not your preference right now.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  7. Back To Top    #7

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

    Re: Before/after 50% refill, still out of balance

    Then again, you'll be using more bleach for the higher required FC. Do a cost benefit analysis.
    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

  8. Back To Top    #8
    Mod Squad YippeeSkippy's Avatar
    Join Date
    Jan 2012
    Location
    'burbs of Augusta, Georgia
    Posts
    6,491

    Re: Before/after 50% refill, still out of balance

    I don't understand these test results:

    Chlorine: 3 (just added 121oz Chlorine an hour before testing)
    Free Chlorine: 4 ppm
    Combined Chloramines: 0
    Total Chlorine (FC+CC): 4

    How can you have 3 Free Chlorine, zero Combined Chloramines yet the Total Chlorine is 4? The math doesn't add up... this isn't some strange Common Core math problem is it? LOL
    My Amazon Smile for November12K Fiberglass IG, Infinity 4000 automatic cover, SWCG, Hayward Sand Filter, Hayward 1.5 Pump, Doheny Discovery Robot, Savi Melody LED pool lights, outdoor speakers and other assorted doo-dads. Sundance Altamar Hot Tub.
    Our pool build--> Our Pool Solved Our Sloping Yard Skippy's Cheap Pool Cooler -->Skippy's New Fountain

  9. Back To Top    #9
    UN1017's Avatar
    Join Date
    May 2012
    Location
    Sacramento, CA
    Posts
    288

    Re: Before/after 50% refill, still out of balance

    Quote Originally Posted by YippeeSkippy View Post
    I don't understand these test results:

    Chlorine: 3 (just added 121oz Chlorine an hour before testing)
    Free Chlorine: 4 ppm
    Combined Chloramines: 0
    Total Chlorine (FC+CC): 4

    How can you have 3 Free Chlorine, zero Combined Chloramines yet the Total Chlorine is 4? The math doesn't add up... this isn't some strange Common Core math problem is it? LOL
    I think tlbig10 was reporting results from the OTO, which look about 3. Then did the FAS-DPD with an FC of 4 and a CC of 0.
    15'x30' IG - Roman-style - 14K - Pebble Fina Classico
    Filter: Jandy CL460 Pump: Jandy Stealth SHPF1.5 SWG: Jandy AquaPure 1400 Cleaner: Jandy RayVac Test Kit: TF-100 w/SpeedStir

    Chlorine/CYA Chart----Extended Test Kit Directions----SLAM

  10. Back To Top    #10

    Join Date
    Feb 2014
    Location
    Phoenix
    Posts
    24

    Re: Before/after 50% refill, still out of balance

    I live in Mesa as well and did a 3\4 drain a few months ago my CYA was off the chart. Once I refilled my CH was close to 550 and TA 200. All I did was lower my PH to 7.2 and maintain that level for the past 2 months now my CH 350 and TA 130. Just keep you PH down and you will be fine. Every time I add water of course my numbers go up a little. As for chlorine my pool is in direct sun all day so I find as it gets hotter I am adding 32 oz a day of 10% chlorine with a Cya of 40.

    1975, 18000 GL, Plaster never been re-plastered, 2 year Old Hayward Sand Filter, Very Old Pump made out of cast Iron, and Single Speed 1 HP motor. Mesa AZ

  11. Back To Top    #11

    Join Date
    Mar 2014
    Location
    Mesa, AZ
    Posts
    2

    Re: Before/after 50% refill, still out of balance

    Thanks for all the support. I will keep this updated with my adventures in pool maintenance. I'll do an analysis on regular water and post my results in here for anyone else in AZ wanting to have an idea of what kind of water we have in the Phoenix area.

    roppy - thanks for letting me know how much chlorine you're adding on a daily basis. I thought what I was adding every three days (120 oz) was excessive, but I'm not too far off. I need to get on the daily check routine and stay on top of it.
    25K gal, sand, IG, plaster, Dolphin Supreme M5 cleaning robot

Posting Permissions

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