Violet/purple Stains-entire pool surface

[scannon]

Hello, from reading posts I think I have copper stains. Can you recommend a good brand either at pool store or online...
light Violet/purple shading stain on entire pool surface, on water line steps darker staining.
Heavy brushing helps a little but still noticeable, think I'll pass out if I have to do entire pool
Thanks for any help.

Pool was green for a 3 months so I tried some "drop n vac" the neighbor suggested- di't help so I tried the slam, cleared up with a slight cloudiness and the stupid purple stains for the last week.
They have never heard of purple stains which kind of scared me.

16k plaster we use liquid chlorine. clean cartridge filter running 9 hours a day

From pool store print out.
FAC 7
TAC 7
CH 200
CYA 70
TA 100
pH 7.3
Copper .6
Iron 0
Phosphates 0
(He said was out of testers for TDS)

Cant seem to upload pics...

 

[Patrick_B]

Hi Scannon and welcome to TFP.

I'll let others answer on the stain remover, but Copper at .6 (if correct) could cause Copper stains. I just don't know about the violet/purple, and not sure I've heard that before. I'm not saying you don't have Copper, but it is less common. Is this an old pool, or do you know about your fill water having Copper? The latter is also pretty uncommon.

As for your testing on the other constituents, I strongly suggest testing your own water with a proper kit. Those results may, or may not be very good. We see a lot of mixed results from store testing and most of us don't trust it as a rule. From here forward, don't worry with TDS. That number on it's own is very arbitrary. It can be somewhat helpful with a salt pool, but I don't know what you have. Could you please add your pool details in your signature so that we can help you better? Let us know, and hopefully we can help.

 

[Swampwoman]

Good morning and welcome. Purplish stains can also be maganese. Are you on we'll water? If so, its possible the maganese was oxidized when you slammed. Either way, whichever metal is causing the stain, you need to sequester the metals.

I would try the "sponge test" recommended in the instructions of proteam's "Metal Magic" --
http://www.poolgeek.com/products/pr...boo-FN51cEWcEVV0Qh00ZvcL98jtcQRBqYaAl_p8P8HAQ

I've had the best luck sequestering metals from my own well (iron, in my case) by starting with a very large dose of this and then adding maintenance levels every few weeks.

By doing the sponge test, you will see if it will ultimately remove the stains, and based on the time it takes, you'll learn how much you need. In my case, I used 5 bottles the first time.

Another option for metal staining is to do an ascorbic acid treatment. There's info how to do this in pool school.

For the latter in particular, (but for upkeep in general) you'll want one of the proper test kits cited here on TFP. You mentioned slamming, but I'm not certain you could have slammed the TFP way if you don't have a test kit. Proper at-home testing is pretty much essential to engage in any of the TFP diy practices.
So I wouldn't try the AA treatment without your own test kit. Its a low chlorine treatment and its important to be able to tell right away if your chlorine is holding during the process where you bring it back up.

So, I suspect the metal magic sponge test would be the easiest immediate way to see if it might work.

Another more expensive way to test stains (but if its maganese, its possible this system is more suited) s to buy Jack's Magic stain ID kit, and then purchase the products based on the outcome of that test.

Jacks Magic and Metal Magic are the two products that TFP generally recommends for any type of metal staining.

Hope that helps get you started!

 

[JamesW]

I would suspect that it is due to copper cyanurate. What can you tell us about the history and chemistry of the pool? At 0.6 ppm, the copper is high enough to cause problems in the right conditions. If the stains are copper cyanurate, then they will contain a significant amount of copper, which would mean that the copper level before the precipitation event was higher.

Are you using an ionizer?
Have you used copper algaecide?