+ Reply to Thread
Results 1 to 10 of 31

Thread: Starting resurfaced pool

Hybrid View

  1. #1
    PoolDoc's Avatar
    PoolDoc is offline Administrator Quark Inspector PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars
    Join Date
    Jan 2005
    Location
    Georgia
    Posts
    11,386

    Default Re: Starting resurfaced pool

    Dichlor in the 55% - 62% available chlorine range is fine; there are 2 'flavors': hydrated and anhydrous. The anhydrous 'flavor' has a bit more chlorine per pound.

    Regarding your TA, you'll probably need to add BOTH acid and baking soda.

  2. #2
    Watermom's Avatar
    Watermom is offline SuperMod Emeritus Quark Inspector Watermom 4 stars Watermom 4 stars Watermom 4 stars Watermom 4 stars Watermom 4 stars Watermom 4 stars
    Join Date
    Dec 1969
    Location
    Charleston, WV
    Posts
    9,345

    Default Re: Starting resurfaced pool

    Judge your use of Borax based on your pH readings.

  3. #3
    Join Date
    May 2014
    Location
    Fort Worth, TX
    Posts
    26

    Default Re: Starting resurfaced pool

    Things are looking better!

    Yesterday morning pool was looking bluer after adding the bleach but TC was low, I added a bit less than 2lb of baking soda to raise my TA then several hours after that after noon added a dose of muriatic acid to lower my pH. In the evening around 9pm, once water had had plenty of time to recirculate with pH and TA in range, I added 2/3 of a pound of dichlor based on my understanding of what is needed for the 14k gallons I have without exceeding the upper limit of what the NPC recommends. 4 hours later, TC had raised a little (0.5) nowhere near the 3ppm I was expecting. Around 1am, I added the same quantity of dichlor again.

    This morning around 8:45am:
    FC 1.6
    CC 0.4
    pH 7.3
    TA 80
    CH 160
    Water temp 80
    SI -0.45

    Tonight I will add another dose of dichlor 55% AC and so on every evening until I run out of the six 1lb bags I got. That should add a tad more than 30ppm of CYA total (if I calculated that right), which should show on the K2006C CYA test. Hopefully by then I get a feeling of how FC/CC last under current conditions, can add some more CYA and switch over to using bleach.

    Questions:
    1/ Once CYA rises, should I cease measuring TA and measure Carbonate Alkalinity instead?
    2/ How much salt/sodium can I expect to add to the pool by recurrently topping off with bleach?
    3/ I have a DE filter and a heater for the hot tub that are both parts of the pool system: I hope dichlor then bleach are ok for use with those, are they?

  4. #4
    BigDave's Avatar
    BigDave is offline Lifetime Member Whizbang Spinner BigDave 3 stars BigDave 3 stars BigDave 3 stars
    Join Date
    Jul 2010
    Location
    New Jersey
    Posts
    1,932

    Default Re: Starting resurfaced pool

    A) 7lbs of dichlor should get you right up to 30.

    1) Does it matter? CYA will affect measured TA consistently. You will raise it if your pH is unstable - you will determine the best level. The CYA component factors out when comparing new TA reading to old, why bother doing the calculation?
    2) A little, maybe 10ppm salt in a jug of bleach.
    3) Just fine - no differrent than any other source of chlorine.
    12'x24' oval 7.7K gal AG vinyl pool; ; Hayward S270T sand filter; Hayward EcoStar SP3400VSP pump; hrs; K-2006; PF:16

  5. #5
    Join Date
    May 2014
    Location
    Fort Worth, TX
    Posts
    26

    Default Re: Starting resurfaced pool

    Thank you BigDave!

    A) Good! At least my calculations are not off ;-)

    1) I see. It's just that the NPC asks for CA not TA to be measured once the pool is started and recommends CA be kept between 80 and 120ppm.

    2) Does that little amount of salt translate into huge amounts over several years? I'm not really sure how to calculate this and don't know if I should bother but I sure wouldn't want to see metals rusting around the pool... I just hope this isn't a bad tradeoff vs using Trichlor and having CYA steadily increasing over the years which in my case and in the past led to algae (as I assume chlorine levels couldn't keep up with high CYA) and to having to empty the pool at least partially. CYA does not evaporate right?

    3) Great. I was wondering as I saw the post about running pools at high pH where dichlor is a source of chlorine never to be used. However I don't think I could easily run my pool at high pH since I have a heater that would perhaps (?) suffer from this.

  6. #6
    PoolDoc's Avatar
    PoolDoc is offline Administrator Quark Inspector PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars PoolDoc 5 stars
    Join Date
    Jan 2005
    Location
    Georgia
    Posts
    11,386

    Default Re: Starting resurfaced pool

    + All forms of chlorine add salt, because -OCl (free chlorine) => O2^ + -Cl (salt) . Bleach adds somewhat more, because it contains free salt, in addition to the chlorine.

    + CYA does not evaporate. It is readily biodegraded however, whenever 'slime' (algae + bacteria) layers form in the pool.

    + Heaters are one place where the SI index actually does matter. You can use the LSI calculator, here, but remember you must use the water temperature at the INSIDE SURFACE of the heat exchanger. A reasonable estimate is the heater effluent temp + 20 degrees F.

    So, if your pool is 75 and the heater effluent is 85, you'd use 105 as the calculation temp. Taking your reported figures, and assuming a TDS of 500 ppm for a freshly filled pool, your POOL has an LSI of -0.26, but your HEATER would have an LSI of 0.1

  7. #7
    Join Date
    May 2014
    Location
    Fort Worth, TX
    Posts
    26

    Default Re: Starting resurfaced pool

    Great info PoolDoc!

    2) So with all forms of chlorine adding some salt, no need to worry about rust with bleach then ;-) Re CYA biodegrading, I will keep an eye on it anyway and can add as needed. I just don't expect much loss if maintenance of FC level prevents slime.

    3) To evaluate the LSI, I have so far used the watergram wheel in the K2006C kit *and* the water temp provided on the display of my Hayward H400FDN heater. I wonder what this temp really corresponds to now that you're mentioning this. I believe it is really close to what the temp is in the pool. Based on your explanation, I understand I only need to adjust the temp reading at the heater by +20 when it runs. I will take a look at the LSI calculator.

    Re vacation/away time, I found a procedure about this on the Super Simple Startup Recipe page that does use polyquat. I guess this is what you were referring to. Interesting.

    Re protozoan cryptosporidium, I found the procedure apparently from the CDC to fight it at this link: http://www.floridahealth.gov/healthy...ponse_reco.pdf

+ Reply to Thread

Similar Threads

  1. Starting up 16x32 AG pool
    By Portland user in forum Pool Startup, Shutdown, & Winter Operation
    Replies: 4
    Last Post: 06-06-2014, 12:37 PM
  2. Help with starting new pool
    By rdefino in forum Testing and Adjusting Pool Water Chemistry
    Replies: 26
    Last Post: 06-02-2014, 09:00 PM
  3. New User Question: Resurfaced Pool - Returns aimed poorly - Suggestions appreciated.
    By shadaway in forum In-Ground Pool Construction and Repair
    Replies: 0
    Last Post: 05-22-2013, 12:03 PM
  4. starting old pool
    By csc138 in forum Pool Startup, Shutdown, & Winter Operation
    Replies: 2
    Last Post: 06-26-2012, 02:44 PM
  5. When is it REALLY time to have the pool resurfaced - and with what?
    By hawkeye91 in forum In-Ground Pool Construction and Repair
    Replies: 1
    Last Post: 01-29-2012, 04:52 PM

Tags for this Thread

Bookmarks

Posting Permissions

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