New Quartz Plaster Stains

[smayala]

Moved from here.

I presume by your pool profile that the pool interior finish is Quartz Aggregate. I would guess that
in the Aggregate there are some Iron Pyrite chips. These will rust and give this type of stain.
You cannot permanently remove the stain with acid as the stain will just return. The only way to
remove the stain is to chip the Pyrite out of the finish. If the pool is new the PB should do this.

Here is how to get ride of these types of stains without draining the pool. Get a 10ft. piece of PVC pipe
about 1" will do. Duct tape a sharp cold chisel to one end of the pipe. You can then use this to chip
out the small spot where the Pyrite chip is located. You must remove the Pyrite completely or the
stain will just re-appear.

Iron Pyrite naturally is found within Quartz strata and can be accidentally mixed with Pebble Tec pebbles
or the various Quartz finishes. In fact one neighborhood here had some of the sand used in Stuccoing
the houses contain some Iron Pyrite and they had to(and still do) paint there houses once a year to gety rid of the
rust stains.

Cliff s

Good morning, we had our pool re-plastered with Quartz last week. I first noticed a few round rust stains while it was filling up and our contractor said it was organic and would all disappear. Yesterday, it was completely filled up and the rust dime size stains were streaking out a bit. The contractor added about 4 gallons of acid, a couple of tablets of chlorine and a bottle of Jack's magic - the magenta stuff. It has been about 16 hours and the stains look exactly the same. I believe it may be the pyrite you mention above but the contractor hasn't even mentioned the possibility. How long would the chemicals take to work on organic stains? Thank you in advance for any advice you can provide.
Sara

 

[Texas Splash]

Sara, personally this doesn't sound like organic to me. Just seems incredibally fast for that to happen, especially during fill. I would be looking at two possibilities:
1 - Metals in the water (i.e. iron or copper)
2 - Something just below the surface of the plaster that may be reacting with the water/chemicals (i.e. rebar) and leaching-out

Can you post a pic of the area and spots you are seeing? I'm also going to ping @bdavis466 who may be able to contribute some advice to your situation.

Sara, please update your signature with all of your pool and equipment info. Also, update your city/state location on the profile and let us know where you get your fill water (city, well, etc). All of this can be valuable info for us to help you.

 

[smayala]

Sara, personally this doesn't sound like organic to me. Just seems incredibally fast for that to happen, especially during fill. I would be looking at two possibilities:
1 - Metals in the water (i.e. iron or copper)
2 - Something just below the surface of the plaster that may be reacting with the water/chemicals (i.e. rebar) and leaching-out

Can you post a pic of the area and spots you are seeing? I'm also going to ping @bdavis466 who may be able to contribute some advice to your situation.

Sara, please update your signature with all of your pool and equipment info. Also, update your city/state location on the profile and let us know where you get your fill water (city, well, etc). All of this can be valuable info for us to help you.

Hi TexasSplash and thank you. The pool is a salt water pool that was built in 2004. The original plaster looked really bad and we decided to go with a quartz plaster for our re-do job. The pump is a Hayward GVA-24 and it was started up about 48 hours ago. We live in a mud district in Spring, Texas so our water quality is not the best. The stains were very small and very round; like the size of a tack head and they appeared about 30 hours into the pool filling up. Later, they streaked out from the circle and they seem to be stuck that way. Is it possible that some of the bags of quartz contained iron contamination? Please see attached pictures and let me know if there is any additional information that I can provide. Thank you.

.

 

[MinerJason]

Hard to tell for sure, but I'm guessing there was some sort of iron sulphide mineral (likely pyrite) in the aggregate mix used to plaster the pool.

 

[smayala]

Hi Jason, that is what I was thinking based on various sites on the subject. Can it be fixed and if so, how?

 

[Texas Splash]

Can it be fixed and if so, how?

As a test, try placing some crushed vitamin C tabs in a thin sock or nylon and place it against the stained area(s). If it's iron, the vitamin c tabs should clear it up quickly. Let us know how it works out.

 

[MinerJason]

Hi Jason, that is what I was thinking based on various sites on the subject. Can it be fixed and if so, how?

If it's something that got onto the surface, like lawn fertilizer, then the vitamin C trick mentioned above should take care of it. If there's pyrite in the plaster aggregate (or another iron sulphide mineral), then the stains will just keep coming back, and the solution might be chipping out each individual piece, or possibly a full re-plaster.

 

[smayala]

I had to go out of town for work but will check with vitamin C as soon as I am back.