Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 4 of 4

Thread: Concerned about CSI

  1. Back To Top    #1

    Concerned about CSI

    I have a 13,000 gal gunite pool, with a SWG. I'm using the ColorQ test kit, and just had it opened for the sprint. I have done a few adjustments, and know have the following readings:
    FC: 4.1
    pH: 7.5
    TA: 74
    CH: 298
    CYA: 40 (need to bring up to 70)
    Salt: 3000
    Borate: 50
    Temp: 45 F

    According to The Pool Calculator, my CSI is alarmingly low, I guess largely due to the temp. If I bring the temp up to the 70's, it's better, although still close to the lower limit. No plans on using the pool for a few weeks, so I hadn't intended on heating it yet. However, now that I see the CSI, I'm wondering if it's doing damage to keep it at these levels for that much time. Do I need to start maintaining a min temp to prevent damage? Or should I not worry about it? Or, is there some other water parameter I should change?

    Thanks in advance for any advice!!

  2. Back To Top    #2
    linen's Avatar
    Join Date
    Jul 2010
    Twin Cities, MN

    Re: Concerned about CSI

    First, I wanted to mention that the experience on this board suggests the ColorQ does not do a great job at measuring cya.

    Have you adjusted you ph down, or is that where you found it? As water gets colder, the ph goes up. This is a good thing when dealing with lower csi.

    For now, I would just bump your ph up to ~8.0 and you should be fine.
    TFP Expert who uses Pool School and my TF100 test kit along with PoolMath for my: Round 11K gallon AGP with deep end, 20" sand filter, Matrix 1hp 2spd, 6 2ftX20ft solar panels (and solar cover!), Intex SWCG (copper bars disconnected) and a Rubadub hot tub (chlorine). The SLAM process is not finished until: 1. CC < 0.5 ppm, 2. An OCLT < 1.0 ppm and, 3. The water is crystal clear.

  3. Back To Top    #3

    In the Industry
    duraleigh's Avatar
    Join Date
    Apr 2007
    Sebring, Florida

    Re: Concerned about CSI

    Almost all of us can keep a crystal clear pool forever without calculating csi. Simply keep your parameters within the guideline suggested and you will not have a problem.
    Dave S. - Forum owner
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  4. Back To Top    #4

    Re: Concerned about CSI

    Thanks for the feedback! I know ColorQ can be difficult to get an accurate CYA reading, but that seems right based on where it was last year, and subsequent partial draining last fall/this spring. I adjusted the pH down, I had been lowering alkalinity after opening. I will let the pH go back up, and leave at that for now. The water *is* crystal clear and looks great, if cold, just wanted to make sure that I wouldn't be harming the plaster.


Posting Permissions

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