Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 3 of 3

Thread: Draining and refilling

  1. Back To Top    #1

    Draining and refilling

    Closed the pool last fall with a CYA of 150 and TA of 180 (pool store test). Last week I began to drain and refill. I shocked with bleach before draining to kill anything still clinging to the walls. Drained to about 3 inches then began refilling. About ½ full I added 96 oz of bleach. Completely full and filter running I vacuumed up a layer of sand and brown residue that covered the bottom. TFT 100 test kit just arrived.
    FC=.5 (one drop turned clear)
    CC=2 (4drops)
    PH = 7.2
    Tonight I added 32 oz of dichlor shock since I still have about 10 bags left from last years fiasco. Tomorrow I will pick up baking soda and bleach.

    Can I continue to shock with the Dichlor since I need to raise the CYA level?
    Also should I add recommended amount of baking soda to get the TA up to 80?
    Then wait till the shocking process is done before retesting and adjusting PH?

    Pool History
    I have had 4 seasons with this pool. Opened and closed using pool store recommended chemicals. I started each season with 150 lbs sand in 200 lb filter. Chlorinated with trichlor pucks through automatic feeder running 8 to 12 hours a day depending on weather , use or looks of water. Target 1-3 ppm based on manufacturers recommend level. Always had evidence of algae on seam where wall meets bottom. It was usually controlled by brushing off 2 or 3 times per week. I have had at least 2 bad outbreaks of algae. At the end of last year it was hopeless so I just closed it. This will be my second time draining and refilling.[/b]
    24 X 52round, Vinyl AGP, 150 lb Sand 1.5 hp filter

  2. Back To Top    #2
    JasonLion's Avatar
    Join Date
    May 2007
    Silver Spring, MD

    Re: Draining and refilling

    You can keep using dichlor, but keep an eye on TA and PH. Dichlor is very acidic, and will lower both PH and TA rapidly if you don't keep up with it.

    I recommend raising TA to 90. You need 9 or 10 lbs of baking soda to raise TA to about 90.

    With TA starting so low and dichlor being so acidic, you can't afford to ignore the PH. Test and adjust PH and TA any time FC levels are below 10 and get them both up soon.
    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

  3. Back To Top    #3

    Re: Draining and refilling

    The drop test kit and pool calculator are great. I got it right the first time.
    Last night FC and CC were at zero.
    I added 9 lbs baking soda and 164 oz of 12.5% liquid shock.
    90 mins later my FC was at 13.5 and CC was .5

    Today I got;
    FC =10
    CC = 0
    PH = 7.2
    TA = 80

    I do not plan on adding anything until the FC drops down. The pool is still mostly covered. I still have some stuff to brush off and vacuum. I may get a jump in the CC with that.
    24 X 52round, Vinyl AGP, 150 lb Sand 1.5 hp filter

Posting Permissions

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