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

Thread: Testing, learning to trust my own eyes

  1. Back To Top    #1

    Join Date
    Oct 2011
    Location
    New Caney, Texas
    Posts
    414

    Testing, learning to trust my own eyes

    I had an interesting day. I had a hard time being sure about my CYA and Ph test levels so I headed to town to get a free pool store water test.
    I went to three different stores in two towns (all close to me). Below are all the readings.

    Mine
    Ph 7.5
    FC 4.5
    TA 60
    CH 120
    CYA 30
    Bor 50

    Store 1
    Ph 7.6
    FC 3.5
    TA 66
    CH 190
    CYA 68
    Bor 58

    Store 2
    Ph 6.5
    FC 4.0
    TA 100
    CH 150
    CYA 90
    Bor No test

    Store 3
    Ph 7.8
    FC 5.0
    TA 90
    CH 200
    CYA 40
    Bor No test

    I didn’t report Salt here as I know it’s slightly low but waiting until I can run the SWCG in the spring.

    The one with the FC of 3.5 (Store 1) wanted to sell me some chlorine neutralizer. And stuff to raise the alkalinity. Quote (3.5 can ruin my vinyl over the winter.)

    The one with 4.0 Chlorine (store 2) wanted to sell me some something to increase the CH to 200.

    I guess I need to trust my own readings (eyes).
    18' x 42" Intex (4786 Gal @ 80% capacity) Intex 8110 SWCG, 2000 GPH cartridge filter.
    Full Sun, Well Water, Borates at approx. 50
    TFTestKit-100--The Pool Calculator--Pool School

  2. Back To Top    #2

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Testing, learning to trust my own eyes

    I guess I need to trust my own readings (eyes).
    Right on the money! There is no one who cares about the accuracy of your tests as much as you do and, surprisingly, there always seems to be wide discrepancies in pool store testing.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  3. Back To Top    #3

    Join Date
    Oct 2011
    Location
    New Caney, Texas
    Posts
    414

    Re: Testing, learning to trust my own eyes

    I can't hardly tell the difference between the 8.2 and the 7.8. I guess I'll keep it in the 7.5
    The CYA is hard to tell with or without my glasses but I think I'll manage.
    18' x 42" Intex (4786 Gal @ 80% capacity) Intex 8110 SWCG, 2000 GPH cartridge filter.
    Full Sun, Well Water, Borates at approx. 50
    TFTestKit-100--The Pool Calculator--Pool School

  4. Back To Top    #4

    Re: Testing, learning to trust my own eyes

    lol, the different readings kills me. Goes to show the how simple messing up a test can be. SOO many things to pay attention to when doing the test right. One time i kept getting weird alkalinity readings even though all the solutions were new. I was refilling them from larger containers. It was the DPD #9 solution! The sulfuric acid had slowly made a bigger hole and gave everyone low alkalinity readings!

    Anyhow, Keep adding a PH reducer until it looks like a nice PEACH color. Slightly red is a little high. Have a women read it, cause men can be color blind to reds. Women can be color blind to Yellow...if using OTO still.
    BTW 1-1/3 cups = 1lb sodium bisulfate, careful not to over add. And I think its only 1/4lb for that size pool?? 1/3 cup per dose per 2-4 hours. If you use acid demand, 2 drops = 1 dose.

  5. Back To Top    #5

    Re: Testing, learning to trust my own eyes

    btw, store 1 is probably the closest...

    You do have low alkalinity and calcium hardness.... Fix the alkalinity for sure. If you really care about your intex pool and plan on having it for years then raise the calcium. Low calcium will damage the liner slowly over time. Chlorine over 4 damage the liner though... ya maybe. Never float tablets, thats for sure, they will slowly kill the liner. Vynl liner manufactures recommend .5-2ppm CL or it degrades the liner. Very tough to always have it there...

  6. Back To Top    #6

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Testing, learning to trust my own eyes

    I would leave your pool right where it is. There is little evidence to show that lack of CH is harmful to a vinyl pool. Your pH is fine.

    A "peach" color on the vast majority of pH tests would indicate a pH of lower than 7.0....don't do that.

    At some point this summer, you may choose to increase your CYA but I would leave your pool alone for now.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  7. Back To Top    #7

    Join Date
    Oct 2011
    Location
    New Caney, Texas
    Posts
    414

    Re: Testing, learning to trust my own eyes

    Appreciate all the help. I do plan to leave as is for now then when the temps warm add CYA and salt before turning the SWCG back on. I must say its fun learning all this.
    18' x 42" Intex (4786 Gal @ 80% capacity) Intex 8110 SWCG, 2000 GPH cartridge filter.
    Full Sun, Well Water, Borates at approx. 50
    TFTestKit-100--The Pool Calculator--Pool School

  8. Back To Top    #8

    Join Date
    May 2011
    Location
    Clearwater, FL.
    Posts
    446

    Re: Testing, learning to trust my own eyes

    Hi George N,
    Stay the course with your TF-100 kit!
    In my Intex 16 X 48 I had about 110 TA in the beginning, but my PH was always going up to 7.8-8.0
    I followed advice from Dave and some of the other mods here (pool school gives a procedure) and lowered it down to 90. My PH now stays steady 7.5-7.6
    My Intex pool see's about 65-70% of sun during the day.
    My numbers were really consistent most of the summer, with a little up and down with chlorine swinging from always having big pool party's (like every weekend/Pool has been perfect for swimming)
    FC averaged 3.5, mostly 3-5 range (up to 7 after some heavy dosing from the party's)
    CC was 0 to .5 almost all the time (once or twice I saw 1 but this was in the evening after a big party or the next day after a good dosing)
    PH was always 7.5-7.6 if I tested while everyone was in the pool or just after, it read a bit higher but would settle right back the next day.
    CH has been between 240-260 every time I checked it (5 or 6 times I tested for it)
    CYA 40-45 every time I checked it after getting it in there with a sock and using the pool calculator (used 4300 gals).
    My temps were between 80-88*F all summer.

    I would think that a little more TA for your pool if your NOT running a SWG and I'm guessing it wouldn't hurt if the CH was up to 200-250, although it has been a general concision here that it's no big deal for my vinyl pool.

    Chuck
    Swim n Play 21' round, expandable 72" liner, 6FT deep center, buried 14", 12,750 Gallons
    Waterway 1HP-2 speed with 22" Sand filter
    TF-100 test kit
    Thanks to TFP my pool is perfect all the time :party:
    I now suffer from Sparklypoolitis! :whoot:
    I am a Platinum contributor because I want everyone who comes here to Trouble Free Pool to have the same success that I enjoy with my pool and family.

  9. Back To Top    #9
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Testing, learning to trust my own eyes

    Trust yourself.

    For what it's worth, I have the best luck reading pH by holding it out at arm's length and sorta squinting, so it gets a little fuzzy to where I can't read the black numbers, with a white backdrop some distance behind. In my case, one of those cheap resin stacking chairs.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  10. Back To Top    #10

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: Testing, learning to trust my own eyes

    Quote Originally Posted by ProPoolGuy
    You do have low alkalinity and calcium hardness.... Fix the alkalinity for sure. If you really care about your intex pool and plan on having it for years then raise the calcium. Low calcium will damage the liner slowly over time. Chlorine over 4 damage the liner though... ya maybe. Never float tablets, thats for sure, they will slowly kill the liner. Vynl liner manufactures recommend .5-2ppm CL or it degrades the liner. Very tough to always have it there...
    There was a technical discussion about calcium levels and vinyl in this thread as well as others. The main detriment to vinyl is low pH, not chlorine or calcium. Chlorine is especially not an issue when there is CYA in the water that significantly lowers the active chlorine (hypochlorous acid) level.
    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
  •