Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 7 of 7

Thread: wierd readings....

  1. Back To Top    #1

    wierd readings....

    pool is 20ft by 10ft, sloping in the center with 3ft ends/5.5ft center. everything was fine until I ran out of trichlor tabs, chlorine level dropped to 0 and started using the trichlor plus tabs instead. here's the reading....
    total hardness- very low
    TC 0
    FC 0
    ph <6.8
    alkalinity 180
    stabilizer very low
    some green algae on the walls despite 1 bottle 50% algaecide

    is it possible to be acidic and have a high alkalinity? I checked it with 2 different brands of sticks and it's accurate
    any ideas??
    thanks

  2. Back To Top    #2

    Join Date
    Feb 2008
    Location
    Denton, TX
    Posts
    5,061

    Re: wierd readings....

    Welcome to TFP!

    You can get your pool squared away with a little knowledge, some simple chemicals, and a good test kit.

    Start reading Pool School (link on the top right of every page). Get a TF-100 test kit from TFTestKits (link in my sig). You can use a pool store temporarily for testing numbers. We need to know: FC, CC, pH, CYA, TA, CH.

  3. Back To Top    #3

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,078

    Re: wierd readings....

    Welcome to the forum

    I checked it with 2 different brands of sticks and it's accurate
    Not necessarily. Strips really have a bad reputation for being able to do the kind of precise testing needed to manage your pool effectively.

    While you are deciding on a test kit, I would double check that pH reading and, if a drops based test confirms it's below 7.0, you need to get the pH up to around 7.4 right away using 20 Mule Team Borax.....found in the Laundry section of most grocery stores.

    Reading the basic articles in Pool School will get you headed in the right direction and will very likely prompt a few questions.....we'll help answer.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  4. Back To Top    #4

    Join Date
    Jan 2010
    Location
    Central Valley, CA
    Posts
    233

    Re: wierd readings....

    chopstick1, welcome and stick with the mods' advice here and you'll be on your way in no time. Unlike the pool store, no one here has a vested interest in you buying product. You do need to buy a good test kit, as already stated, but that is well worth it. I knew nothing about pools before last year. Found this website and read pool school, etc. and have never had a lick of trouble.
    Garden Leisure Voyager 12x24 AGP, 7500 Gallons, Hayward Power Flo Matrix 1 HP pump, dual speed, Hayward XStream Cartridge Filter, 120 GPM,

  5. Back To Top    #5

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

    Re: wierd readings....

    Quote Originally Posted by Sportsman
    Unlike the pool store, no one here has a vested interest in you buying product.
    True for chemicals; not true for test kits. The owner of TFP is also the owner of TFTestkits. The test kits are good with an economical balance for reagents you use the most, they are based on Taylor reagents, shipping is extraordinarily fast, and service is superb. You can look at Test Kits Compared in the Pool School. Regardless of the drop-based FAS-DPD test kit you use, the information regarding the poor resolution and quality of test strips is still valid (a detailed comparison of test strips and their flaws is in this post).
    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"

  6. Back To Top    #6
    Ohm_Boy's Avatar
    Join Date
    May 2007
    Location
    Orlando, FL
    Posts
    1,344

    Re: wierd readings....

    Quote Originally Posted by chopstick1
    pool is 20ft by 10ft, sloping in the center with 3ft ends/5.5ft center. everything was fine until I ran out of trichlor tabs, chlorine level dropped to 0 and started using the trichlor plus tabs instead. here's the reading....
    total hardness- very low
    TC 0
    FC 0
    ph <6.8
    alkalinity 180
    stabilizer very low
    some green algae on the walls despite 1 bottle 50% algaecide

    is it possible to be acidic and have a high alkalinity? I checked it with 2 different brands of sticks and it's accurate
    any ideas??
    thanks
    Yes, it is possible to have low ph and high total alkalinity. The two, confusingly enough, aren't the same. Your ph appears to be extremely low - 6.8 is the bottom of your measurement scale, and it is unknown how far below that your ph is, really. You should get some borax in the water now. As mentioned above, 20 Mule Team borax is the stuff.
    Your ph needs to be between 7.2 and 7.8. Do this first.

    Total Alkalinity is more of a measure of the resistance to ph change of your water. We can address that later.

    As you know, you have no chlorine in your pool. As soon as you get the ph in range, you should dose your pool with liquid chlorine. The reason for not using tablets or powder is that every other type of chlorination product adds additional ingredients - dichlor powder and trichlor tabs (what you have been using) add CYA, and cal-hypo adds calcium. Liquid chlorine, sodium hypochlorite, or ordinary unscented laundry bleach, just adds chlorine.

    And, since you have been using trichlor, it is highly probable that your stabilizer is not low, but quite high.

    I will also again mention the need for a good test kit. Strips are notoriously inaccurate and often worse than no test at all. Pool store tests can be decent, but more likely are haphazardly done by people who do not care about good results using poor test equipment. In fact, the worse your results with them, the more money they make.
    Do yourself a favor and get a quality drops-based kit, preferably one which has a FAS-DPD chlorine test. The only two I know of is the Taylor K-2006 and the TF100. The two are compared here: pool-school/pool_test_kit_comparison

    Note that FAS-DPD is different from DPD.

    And welcome to TFP.
    [center:1kpalu48]Helpful Links: Pool School | CYA/Chlorine Chart | Pool Calculator[/center:1kpalu48]

  7. Back To Top    #7

    Join Date
    Jun 2010
    Location
    Glendale, CA
    Posts
    513

    Re: wierd readings....

    A good test kit absolutely is the best investment I've made in a long time.

    I would doubt those stick results : for example it is doubtful that your CYA level is very low if you have been using pucks for years. Unless you've replaced most of your water recently. (Ohm beat me too it )
    16K Gal Plaster | Compupool SWG | Intelliflow VF | TF-100

Posting Permissions

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