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Thread: Calcium problem?

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    Calcium problem?

    My calcium level was always over 500 and even over 700 with tf test kit. Today it is either 500 or 600 (did the test 4 times and finally out of 0012).

    Do I have to wait a second or two between drops when I use speedstir? I think I may have done it too fast and may be that can explain why I got two different results.

    We had lots of rain and lots of hot days this season, so I drained (from the top, during rain) and added about 8-12" of water (pool 23k plaster)

    I've done probably about 20 tests in 5-7 pool stores in last 2 years and stores almost always see my calcium level under 500 and only a couple of times reading was over 600 or even 700. Some of the stores use taylor kits, while others use strips with reading machines. Last year one of the Leslie's guys kept saying to his workers that the testing should be stopped if they see these undissolved particles (pic attached). He'd say it has something to do with other metals and there's no point to continue. Then he would take over, re-test and cross out 6xx reading entered by other employee and write between 200-400. other employees said they have never seen these particles before, some claiming they've been doing it for 10 years. I never paid attention to these, or I should say never noticed these when I was doing the test myself. Today I turned off the speedstir and sure enough I see them, but I see them with agent 0011 and 0012 and I'm not even sure now at what point the store used to see them. Can someone shed some light on this?

    Also, two of the pictures show a very porous spot on my pool wall. I don't know how old it is and wonder if it is calcium. I have a few spots like this oen. I used calcium based shock, about 25lb last year and haven't used it since but I don't know what previous owners used and I have only had Leslie's test my water when I was using this shock and their reading was under 300.

    sorry if pictures are too small. I had to do some editing to make them under 256k
    Attached Images Attached Images
    18'X4' 7600 Gal AG
    3/4 HP Pentair Pump
    Hayward S166T 100 lb sand filter

  2. Back To Top    #2

    Re: Calcium problem?

    Metal ions (usually copper) can cause errors in the calcium hardness test. If you add 5 to 10 drops of reagent R-0012 first, you can usually eliminate the interference. Count the initial drops of R-0012 in the total number of drops needed to change the color from red to blue.
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