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Thread: What to change?

  1. Back To Top    #1

    Join Date
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    What to change?

    Long time lurker, first time poster. I'm new to the BBB method so I could use some advice on what to adjust. I've got a 13,500 gallon pebble pool with a SWG. As of this evening my numbers are:

    FC: 3.5
    CC: 0
    pH: 7.5
    TA: 80
    CH: 270
    CYA: 50
    Temp: 70
    Salt: 3450
    Borates: 50

    This gives me a CSI of -0.5 per the pool calculater.

    My plan was to bring pH up to 7.6, CH up to 300, and CYA up to 70. This will still result in a CSI of -0.42. Beyond this, what should I adjust to bring CSI closer to 0? I've played around with the numbers in the calculator and it appears the only way to get CSI below -0.30 is to take at least one of the other parameters out of the recommended range.

    Thanks!

  2. Back To Top    #2

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    Re: What to change?

    Is your pH stable, or does it tend to go up a lot? If it's stable, you could try raising TA a little.
    Other than that, keeping the pH a little higher seems like the best approach.
    (Boy it feels weird to recommend a higher pH...)
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

  3. Back To Top    #3
    Richard320's Avatar
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    Re: What to change?

    Have you tried plugging in different temperatures? Things will change when it heats up in the summer.
    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!

  4. Back To Top    #4

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    Re: What to change?

    Thanks for the input! pH is relatively stable. At my current levels the temp would have to hit 93 to get CSI under -0.3. If I make the changes I mentioned above I would need a temp of 84. Should I ignore CSI for now and wait for warmer weather?

  5. Back To Top    #5

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    Re: What to change?

    How does the water look?
    45,180 gallon 26' x 53' IG Vinyl, irregular shape. Hayward sand filter / pump. Polaris AutoClear SWG, supplemented with a Hayward Automatic Chlorinator (In-Line). Hayward 400K BTU heater. Paramount "turnover" system. Polaris 480 PRO cleaner.

  6. Back To Top    #6

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    Re: What to change?

    The water looks and feels great. It's crystal clear with no hint of problems. The kids have already been swimming twice this week.

  7. Back To Top    #7
    JasonLion's Avatar
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    Re: What to change?

    You actually want the CSI to be a little negative, not at exactly zero. Almost all of the natural variation in the levels is towards higher CSI levels. You need some "head room" to allow for unpredictable occurrences. For example, PH almost always goes up over time, especially with a SWG. CSI is also significantly higher inside the SWG cell.

    I would raise CH up to around 300 to 320, and CYA to between 70 and 80 and leave everything else alone. The PH will drift up on it's own eventually.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  8. Back To Top    #8

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    Re: What to change?

    This will be our first summer with a pool. I'm trying to learn as much as possible as quickly as possible so the input is greatly appreciated.

    I remember reading in another thread that as you add water to offset evaporation your CH will go up. I'm in Texas so I'm anticipating a fair amount of evaporation in June, July, and August. If I want CH to be at 300-320 should I try to get there now or let it naturally happen over time as I add water?

  9. Back To Top    #9

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    Re: What to change?

    What's the CH of your fill water? How fast the pool's CH goes up will partly depend on what you're replacing the evaporation with.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

  10. Back To Top    #10
    JasonLion's Avatar
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    Re: What to change?

    Measure your fill water CH level to see if this will be an issue for you. In much of Texas there won't be any issues. High CH level problems are much more common in places like Arizona and Nevada, though they can happen in some parts of Texas.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  11. Back To Top    #11

    Join Date
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    Re: What to change?

    I'll measure the fill water tonight. Thanks so much, guys. This site is awesome!

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