Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 10 of 10

Thread: Why Acid Wash New Quartz Pool Finishes?

  1. Back To Top    #1

    Join Date
    Jul 2011
    Location
    Arizona & California
    Posts
    771

    Why Acid Wash New Quartz Pool Finishes?

    It is understood that muriatic acid can dissolve and etch a plaster surface. Therefore, why, after a plastering finisher works hard to achieve a smooth, hard, brand-new, hand-crafted, quartz pool-finish, would anyone immediately perform an “acid wash or acid bath” on that pool and that plaster? Yes, doing so can increase the exposure of the quartz color; but isn’t that removing some plaster material and shortening the life of the plaster and leading to future problems?

    Although acid washing of older plaster pools can be helpful to remove stains and scale, an acid process, unfortunately, will make the surface more porous, rough, and prone to future streaking, blotchiness, and staining over time.

    If a new plaster surface begins to show blotchiness, streaking, or dirty brown stains a few months after completion, the acid wash or acid bath treatment that was performed when the pool was new may be the cause of those discoloration problems.

    As is known, new plaster/quartz pools can be more easily damaged by acid than one that is a few months old. That is why the NPC recommends the Traditional Start-up program in order to prevent acidic and aggressive water from damaging a new finish.

    Fortunately, there are better methods that will achieve exposure of the quartz color and retain a smooth and durable surface without damaging the pool finish.

    Step 1: During the plastering process, properly time the hard troweling process to remove the weak, watery cement “cream” (known as laitance) that develops on a cement/plaster surface. The cement cream that accumulates on the hand-trowel while hard troweling should be discarded. Do not leave a thin layer of cream on the surface while troweling, which not only prevents the color of the quartz from showing, but creates a weakened surface that will break down, deteriorate, and likely become unsightly over time.

    It is commonly believed that as plaster hardens and “cures,” it will naturally release a cement component known as calcium hydroxide, which then results in the common “plaster dust” forming throughout the pool. However, that is not necessarily true, and can be prevented.

    Calcium hydroxide can be prevented from leaving the plaster surface in the first place, and instead, be chemically converted into calcium carbonate (a much harder material) within the plaster matrix. When this is achieved; the surface is harder and smoother, and no plaster dust develops to foul the surface.

    Step 2: Preventing calcium hydroxide from leaving a plaster surface can be achieved by the following. Create a “thick” plaster mix (with a low water/cement ratio), do not add calcium chloride, and do not add water to the plaster surface and trowel it into the surface. Delay the start of filling of the pool for at least 6 to 8 hours after completing the finishing and plastering process. (If the weather is hot and dry; tent the pool!) Fill the pool with +0.5 LSI water. (The Bicarb Start-up recommended by onBalance will accomplish that).

    Step 3: A pool cleaner can be used to continually polish the plaster surface over time to maximize the quartz or pebble color.

    If the above recommendations are followed, there will be no need to perform an acid wash or an acid bath (also known as Acid Start-up or Zero Alkalinity Process) after the pool has been filled in order to eliminate plaster dust problems and expose the quartz color.

    The benefit of following the above recommendations is a pool finish that is smooth, dense, durable, and stain resistant. The color of quartz will be vivid, consistent, and long-lasting, and that is what will make a pool owner willing to pay a premium for a special quartz finish.

    The picture below of a quartz pool shows the color of the blue quartz pool finish. That pool finish (pictured) is ten years old, had no CC added to the original plaster mix, no wet/water troweling was allowed, had a 12 hour delay water filling start, and was started up (filled) with the Bicarb Start-up chemical process. An acid wash or acid bath treatment has never been performed on this quartz pool.

    KimQuartz3.jpg
    Last edited by onBalance; 04-07-2017 at 12:53 PM. Reason: Edited for improved clarity

  2. Back To Top    #2

    Join Date
    Jan 2013
    Location
    Houston, TX
    Posts
    1,079

    Re: Why Acid Wash New Quartz Pool Finishes?

    GREAT post! Thank you.
    TFP Moderator Chris V. ~16K Pool & Spa, 48NSF DE, IG Plaster Circa 2000, Intermatic PE653, Challenger pump with a 2 speed B2984, 20gal stenner chlorine injection, Houston, TX
    One cannot follow Islam and Christianity at the same time, nor can one follow pool store methods and TFP at the same time.
    Pool School -- Pool Math -- TF-Test Kit

  3. Back To Top    #3

    Join Date
    Apr 2017
    Location
    Los Gatos, CA
    Posts
    5

    Re: Why Acid Wash New Quartz Pool Finishes?

    Hello onBalance,

    Do you know of any pool resurfacer or any pool remodeling company (Burkett's, Adams, Aqua Gunite, California's Gunite) that will follow your installation "No acid wash" guidelines when doing a Quartz pool resurface in the Bay Area in California? I am located in San Jose, California (Los Gatos to be exact, 95032) and I am ready to schedule a pool remodel of our lazy "L" shaped pool. The pool is 122 liner feet around the perimeter so it is a fairly large 30,000 or more gallon pool. I really want to use the EcoFinish product called Aquabright to resurface but there are no installers in my area as all of them are down in LA about 300 miles away. Any insight or recommendations you can provide would be appreciated.

    Thanks,
    Scott

    Quote Originally Posted by onBalance View Post
    It is understood that muriatic acid can dissolve and etch a plaster surface. Therefore, why, after a plastering finisher works hard to achieve a smooth, hard, brand-new, hand-crafted, quartz pool-finish, would anyone immediately perform an “acid wash or acid bath” on that pool and that plaster? Yes, doing so can increase the exposure of the quartz color; but isn’t that shortening the life of the plaster and leading to and causing future problems?

    Although acid washing of older plaster pools can be helpful to remove stains and scale, an acid process, unfortunately, will make the surface more porous, rough, and prone to future streaking, blotchiness, and staining over time.

    If a new plaster surface begins to show blotchiness, streaking, or dirty brown stains a few months after completion, the acid wash or acid bath treatment that was performed when the pool was new may be the cause of those discoloration problems.

    As is known, new plaster/quartz pools can be more easily damaged by acid than one that is a few months old. That is why the NPC recommends the Traditional Start-up program in order to prevent acidic and aggressive water from damaging a new finish.

    Fortunately, there are better methods that will achieve exposure of the quartz color and retain a smooth and durable surface without damaging the pool finish.

    Step 1: During the plastering process, properly time the hard troweling process to remove the weak, watery cement “cream” (known as laitance) that develops on a cement/plaster surface. The cement cream that accumulates on the hand-trowel while hard troweling should be discarded. Do not leave a thin layer of cream on the surface while troweling, which not only prevents the color of the quartz from showing, but creates a weakened surface that will break down, deteriorate, and likely become unsightly over time.

    It is commonly believed that as plaster hardens and “cures,” it will naturally release a cement component known as calcium hydroxide, which then results in the common “plaster dust” forming throughout the pool. However, that is not necessarily true, and can be prevented.

    Calcium hydroxide can be prevented from leaving the plaster surface in the first place, and instead, be chemically converted into calcium carbonate (a much harder material) within the plaster matrix. When this is achieved; the surface is harder and smoother, and no plaster dust develops to foul the surface.

    Step 2: Preventing calcium hydroxide from leaving a plaster surface can be achieved by the following. Create a “thick” plaster mix (with a low water/cement ratio), do not add calcium chloride, and do not add water to the plaster surface and trowel it into the surface. Delay the start of filling of the pool for at least 6 to 8 hours after completing the finishing and plastering process. (If the weather is hot and dry; tent the pool!) Fill the pool with +0.5 LSI water. (The Bicarb Start-up recommended by onBalance will accomplish that).

    Step 3: A pool cleaner can be used to continually polish the plaster surface over time to maximize the quartz or pebble color.

    If the above recommendations are followed, there will be no need to perform an acid wash or an acid bath (also known as Acid Start-up or Zero Alkalinity Process) after the pool has been filled in order to eliminate plaster dust problems and expose the quartz color.

    The benefit of following the above recommendations is a pool finish that is smooth, dense, durable, and stain resistant. The color of quartz will be vivid, consistent, and long-lasting, and that is what will make a pool owner willing to pay a premium for a special quartz finish.

    The picture below of a quartz pool shows the color of the blue quartz pool finish. That pool finish (pictured) is ten years old, had no CC added to the original plaster mix, no wet/water troweling was allowed, had a 12 hour delay water filling start, and was started up (filled) with the Bicarb Start-up chemical process. An acid wash or acid bath treatment has never been performed on this quartz pool.

    KimQuartz3.jpg
    Lazy L plaster pool, 122 liner feet, soon to be Aquabright...Hopefully, if I can find an installer.

  4. Back To Top    #4

    Join Date
    Jul 2011
    Location
    Arizona & California
    Posts
    771

    Re: Why Acid Wash New Quartz Pool Finishes?

    I know of a quality pool builder in your area that highly recommends and uses Adams Pool Specialties for his various pool plastering jobs.
    Give them a call and talk with them about this and see if they will work with you.

  5. Back To Top    #5

    Join Date
    Jun 2016
    Location
    East Central MS
    Posts
    94

    Re: Why Acid Wash New Quartz Pool Finishes?

    Is the same process applicable for Pebbletec or any other pebble finish? I'm guessing it might void the warranty?
    34K gal, 20'x40' IGP (backfilled and reinforced concrete block walls with concrete floor built mid-1970's; renovated 2017), PebbleSheen Arctic White plaster finish, Lotus Prisma Marine 1x2 glass waterline tiles, Indiana limestone coping, 1.5hp Hayward pump, Pac-Fab Triton TR100 sand filter, Pentair Intellibrite 5g color LED 120v Pool Light, Dolphin Supreme M400 robot

  6. Back To Top    #6

    Join Date
    Jul 2011
    Location
    Arizona & California
    Posts
    771

    Re: Why Acid Wash New Quartz Pool Finishes?

    If I understand your question, if no acid wash procedure is done on a pebble type finish, I don't see how that can void a warranty of the product.

  7. Back To Top    #7

    Join Date
    Jun 2016
    Location
    East Central MS
    Posts
    94

    Re: Why Acid Wash New Quartz Pool Finishes?

    Only because they a specified application process was what I was thinking. Would you say there is also no reason to acid wash a pebble finish? They claim to do it to "expose" the aggregate.
    34K gal, 20'x40' IGP (backfilled and reinforced concrete block walls with concrete floor built mid-1970's; renovated 2017), PebbleSheen Arctic White plaster finish, Lotus Prisma Marine 1x2 glass waterline tiles, Indiana limestone coping, 1.5hp Hayward pump, Pac-Fab Triton TR100 sand filter, Pentair Intellibrite 5g color LED 120v Pool Light, Dolphin Supreme M400 robot

  8. Back To Top    #8

    Join Date
    Jul 2011
    Location
    Arizona & California
    Posts
    771

    Re: Why Acid Wash New Quartz Pool Finishes?

    Fresh plaster can be removed and the aggregate (the aggregate is not affected by acid) can be sufficiently "exposed" with just washing or rinsing with water and without using acid.

    I believe that using acid is over-doing it, and causing too much damage. But that it what pebble companies think is best to expose the color of the pebbles. They seem to be more concerned about "color" than the long-term effect of using acid on fresh plaster/cement which makes the cement portion more porous at surface. But note that many dark color pebble plaster pools soon turn whitish/blotchy afterwards. And they don't see the connection. When "porosity" develops, it is always lighter in color.

    It is just assumed that the water chemistry is off and scale is developing. When something goes wrong, it is always easy to blame the water maintenance.

  9. Back To Top    #9
    bcrail's Avatar
    Join Date
    Sep 2016
    Location
    Cross Roads, TX
    Posts
    4

    Re: Why Acid Wash New Quartz Pool Finishes?

    Wish you had done my pool. The quartz finish after 10 months is a mess of blotchy, dark marks, white marks, bright blue marks. I am angry. B

  10. Back To Top    #10

    Join Date
    Jul 2011
    Location
    Arizona & California
    Posts
    771

    Re: Why Acid Wash New Quartz Pool Finishes?

    If you are interested in some help with this plaster problem, please start a new thread in this Deep End section and post two or three pictures, and with any background information that you think might be helpful.

Posting Permissions

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