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

Thread: Confirmation on test and calculator use

  1. Back To Top    #1

    Join Date
    Jan 2010
    Location
    Southeast Missouri
    Posts
    33

    Confirmation on test and calculator use

    Below are my first set of readings. Water was 66 F, ambient temp also 66 F. Sample taken into house for testing.

    FC 4.0
    CC 0
    TC 4.0
    pH 6.8
    TA 80
    CH 260
    CYA 50

    Pool calculator said to add 68 oz by volume of soda ash to raise pH to 7.5.
    I know soda ash will also increase TA so I only added half the amount (34 oz) and will retest to see where that takes TA. Then either use soda ash or borax to get pH to 7.5.

    Does this sound right? Also, with no CC do I still need to raise chlorine to shock level of 20 (CYA of 50) or just up to target level of 6?

    Thanks in advance for any help. You have all been very helpful so far!! I love this site!
    Dave in Sikeston, Mo.
    27' AG, 16K, vinyl, 1.5 HP pump, Pentair Meteor sand filter, Hayward Aqua Rite 25K SWG, Pentair E-Z Vac cleaner, TF100 test kit

  2. Back To Top    #2

    In the Industry
    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    28,415

    Re: Confirmation on test and calculator use

    npgm,

    If you meet these guidelines (and it sounds like you will), there is no reason to shock your pool

    1. Your pool water is sparkling
    2. Your CC's are .5ppm or less
    3. You can hold your FC overnight without losing more than 1ppm.

    Those are really excellent numbers (with your pH adjustment). Did you open with those?
    Dave S. - Forum owner
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  3. Back To Top    #3
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,887

    Re: Confirmation on test and calculator use

    If the water is clear and clean and there isn't any CC then there is no need to shock.

    A PH result of 6.8 is tricky because most PH testers will read PH levels below 6.8 as if they were 6.8. So your PH might actually be lower than you think it is.

    For now, the important thing is to get the PH above 7.0 fairly quickly. Then you can adjust from there more leisurely. If you can get borax, it would be better to use that, but do something to raise the PH today. I would add a box of borax at a time (or 2 lbs of soda ash), give it an hour to mix in and then test the PH and repeat as needed until the PH is higher than 7.0.
    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

  4. Back To Top    #4

    Join Date
    Jan 2010
    Location
    Southeast Missouri
    Posts
    33

    Re: Confirmation on test and calculator use

    Quote Originally Posted by duraleigh
    npgm,

    If you meet these guidelines (and it sounds like you will), there is no reason to shock your pool

    1. Your pool water is sparkling
    2. Your CC's are .5ppm or less
    3. You can hold your FC overnight without losing more than 1ppm.

    Those are really excellent numbers (with your pH adjustment). Did you open with those?
    I will do an overnight FC tonight and see what happens. I know the guy that had this house and pool before me closed the pool and I had no idea what he did. I did find some pH Down in the garage and from my readings he must have used it. I was surprised to see the FC where it was after a long winter. However, I did do some testing before I got the cover off last week and had CYA of 90, TA of 30, and the same low pH. I know without circulation those numbers were suspect, but I do know the previous owner used a lot of either dichlor or trichlor so suspected high CYA. I followed the Pool Calculator advice to do a partial drain to lower the CYA and hit my target of 50, which was way cool. All of this chemistry stuff is new to me but I am enjoying learning about it and hope that one day I can also help others on here. Are you the same person that sells the TF100 kits? I just ordered one of the magnetic stirers and some CYA refill.
    Dave in Sikeston, Mo.
    27' AG, 16K, vinyl, 1.5 HP pump, Pentair Meteor sand filter, Hayward Aqua Rite 25K SWG, Pentair E-Z Vac cleaner, TF100 test kit

  5. Back To Top    #5

    Join Date
    Jan 2010
    Location
    Southeast Missouri
    Posts
    33

    Re: Confirmation on test and calculator use

    Quote Originally Posted by JasonLion
    If the water is clear and clean and there isn't any CC then there is no need to shock.

    A PH result of 6.8 is tricky because most PH testers will read PH levels below 6.8 as if they were 6.8. So your PH might actually be lower than you think it is.

    For now, the important thing is to get the PH above 7.0 fairly quickly. Then you can adjust from there more leisurely. If you can get borax, it would be better to use that, but do something to raise the PH today. I would add a box of borax at a time (or 2 lbs of soda ash), give it an hour to mix in and then test the PH and repeat as needed until the PH is higher than 7.0.
    Hi Jason, Thanks for the quick reply!

    Tested again after adding 34 oz of soda ash and that raised the pH to 7.2 and TA from 80 to 90. I have since added 61 oz (by volume according to pool calculator) of Borax as you suggested and will test again after in an hour.

    If that gets me to pH of 7.6 then I will add enough 6% bleach to get me to my target and see if my FC holds overnight.
    Dave in Sikeston, Mo.
    27' AG, 16K, vinyl, 1.5 HP pump, Pentair Meteor sand filter, Hayward Aqua Rite 25K SWG, Pentair E-Z Vac cleaner, TF100 test kit

  6. Back To Top    #6
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    Location
    SWSuburban Chicago, IL
    Posts
    11,963

    Re: Confirmation on test and calculator use

    Sounds like a plan!
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

  7. Back To Top    #7

    In the Industry
    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    28,415

    Re: Confirmation on test and calculator use

    Are you the same person that sells the TF100 kits? I just ordered one of the magnetic stirers and some CYA refill.
    Yes (Thanks!!)
    Dave S. - Forum owner
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

Posting Permissions

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