Stain Dilemma - Jacks Magic #2 or Acid Wash or ???

[Jbjohnson]

I have a 31000 gallon white plaster pool. Started it brand new 45 days ago. It took 52 hours to fill it up and once it got going it had some stains left on the floor and the walls. After a a month, the pool builder said we should empty the pool, do a light acid wash. We did that and then filled the pool. In our city, after 52 hours, the pool was pretty green. I shocked the pool to remove the organics and after 2 days, the water was and has stayed clear as I balanced it. However, left behind are some light greenish brown stains on the walls and floor(it's worse than before). I have scrubbed, vacuumed, shocked, etc and nothing has changed. I did use Jacks magic stain ID kit and the Jacks Magic Solution #2 worked great in less than 30 seconds to remove the stain on contact. Seems like a no brainer to execute the solution #2 process, but I have read folks have concerns about the phospates added from Jacks Magic. Since it's proprietary I don't know what's in the solution. My plaster guy said he would do a acid wash without draining the pool if I wanted him to before I spent the money on Jacks. I am concerned about re-acid washing the plaster again 45 days after it was plastered. Concerned about weakening the plaster long term.

In talking with the Jacks magic guy he thinks that this is likely a calcium scale which is why the #2 solution worked.

Anybody have a similar situation where you used the #2 solution?
Anyone know what is really in the #2 solution?
Would you try an acid wash first before Jack's, or is there something else I should be considering.

Thanks everyone!

 

[duraleigh]

Sorry you have not received a reply. I cannot help with your issue. Even on this VERY busy forum, there are sometimes questions that no one has a good answer for. Your's might be one of them.

 

[cowboycasey]

I wish that I knew something about this, hope someone else will...

 

[chem geek]

As noted in this post (and this thread), we believe that Jack's Magic Stain Solution #2 The Copper & Scale Stuff is Sulfamic Acid.

First of all, we don't worry about HEDP metal sequestrants that add phosphates to the pool because if you maintain the proper FC/CYA level then the phosphate level doesn't matter because chlorine is killing algae faster than it can grow even under ideal conditions with plenty of algae nutrients (phosphates and nitrates) because algae growth is ultimately limited by sunlight and temperature. Second, this stain solution #2 product does not contain phosphates (or HEDP).

If the stain is a copper stain that is fairly new, then citric acid can usually be used to remove it. You then need to use a metal sequestrant to keep it from restaining, but any standard sequestrant will then work including the HEDP metal sequestrants.

Note that the stain solution #2 product gives an artificial CC reading with low or no FC for up to about a month. This is all described in the Jack's Magic documentation here which I copy below:

If you have difficulty getting a free chlorine reading after doing a STAIN SOLUTION #2 Treatment, test the Total Available Chlorine. Assume this reading is the true Free Available Chlorine reading. STAIN SOLUTION #2 often causes an error in the DPD #1 test; this reaction may last up to a month while STAIN SOLUTION #2 is still in the water.