Question about orange/brown stain...

[PopcornGirl]

Ok, we're still trying to figure this one out...

I have an in-ground, gunite pool (almost 5 years old) & I live in Southeast Louisiana. For the first 3 years, we used an electric, copper ionization system. At the end of the 3rd season, we removed the copper bars and tested the water; it showed almost no copper in the pool. As it was nearing winter, we let the pool filter just run but did not add chlorine until the following spring.
All last summer, we used chlorine with great success! It was SO much easier than the copper ionization system!
This winter, we did not neglect our pool as we previously had, but we didn't keep it completely *up* either... When we opened it 3 weeks ago, there was some leaf debris and algae, but we could see the bottom of the pool and the chemistry was not WAY off...
We vacuumed the pool thoroughly, soaked and rinsed the cartridge filters, and then added acid & (after 3 hours) shocked the pool. Two days later, I added black algetrine because I noticed the black algae trying to come back (a problem that was introduced during our copper ionization days). Our calcium hardness was a bit low, so we added that a couple of days later. All of our levels are now *perfect*, and the black algae is all but gone, but there is this stubborn, orangish-brown stain on the bottom of my pool and at the base of the walls (where the floor curves up into the wall). The walls are pristine; no algae or stains at all.
I have scrubbed and scrubbed. The local pool store is baffled. Then I reminded them that we used to use copper so they tested for that and it came back positive! HOW is that possible??? It's been almost 2 years since we have actively added copper to the pool. I know some algaecides use copper; did the black algaetrine do this? Is this stain even related to the copper level in my pool or is it something else entirely?
I could really use some input here; I'm still a bit of a novice at all this and I don't want to do anything wrong & really screw up my pool.
One final note (sorry to be so long-winded): Yesterday (per my pool store's instruction), I added 1 quart of Metal-Out to my pool with the instruction to wait 2 days, rinse my cartridge filters, and then repeat the process. It has been nearly 24 hours since I added the Metal-Out and there has been no noticeable change in the stain so I'm wondering if this is even the right course...
I truly appreciate any help or direction you can give me!
Thanks in advance,

[PopcornGirl]

Here are some pics I took the other day of the stained areas...
Any thoughts???

MyPool

[waterbear]

I am not an expert on metals in pools but I do have bit of a chemistry background. Your stains look more like iron than copper based on the color. Copper strains are usually blue to black. I am sure your water tests positive for copper unless you have drained and acid washed your pool you probably have a coating of copper deposited in your pool from your ionizer. Could your fill water have a high iron content? I have read posts on here on using ascorbic acid (vitamin c) to remove the stains and I know that many of the commercial stain removing products the pool stores sell are just ascorbic acid. Try taking a vitamin C tablet and holding it on the stain and see if the stain goes away. If it does then you know what you need to treat the stain. A sequestering/chelating agent usually will not remove a metal deposit. It only ties up metal ions in the water so they do not percipitate out as a stain.
Hope I've been of some help.

[duraleigh]

Hi, Summer,

I have never had a metal issue but I think "Waterbear"'s post has it just right. It certainly looks like iron to me and the cure I see on this forum time and time again is vitamin C. It's available in bulk and I've seen folks here post where to get it but I can't remember. Someone will post soon, I'm sure.

Dave S.

P.S. be cautious about shocking 'til you get the iron (if it's iron) out of the pool.

[PopcornGirl]

Thanks so much for your replies, Waterbear & Dave! I really appreciate your help.
I had not considered iron...
But where is it coming from??? We are on municipal water and Baton Rouge's water is notoriously SOFT (aggravatingly so!).
Also, I am not a scientist (my degree is in history ) but why wouldn't Metal Out remove iron from the water?
Finally, I know NOTHING about using ascorbic acid... do I need to stop the chlorine (I use a feeder with the discs) and do I need to let the chlorine level drop before adding the asc. acid?
I'm sorry to be such a novice; this is all still very new to me!
Thanks again,

[waterbear]

Soft water just removes calcium hardness. It has nothing to do with any possible dissoved metals which can come from numerous sources such as pipes, the ground your water source comes from, pollution, etc. It is possible to have soft water with a high iron content. First step would be to check your water for all metals. I have a big distrust of pool store testing from my own experiences. One time I brought in two different samples, one from my spa and one from my pool, and did not tell them that they were a connected system and that I had my spillover running for 4 hours right before I took the samples. One sample tested as having very low CYA and the other sample was low on CH and had very high TDS. I suspect it was error on the part of the (what looked like) high school girl who was doing the testing. There is a compnay that is supposed to make a metal stain identifying kit (I think it's Jack's Magic but I don't know anything about it) and Taylor sells kits for testing for varous metals as do other testkit companies (LaMotte). There might even be test strips that will at least tell you if metals are present but I would not trust them to tell you at what concentration. Iron is your most likely culprit and you probably still have a lot of copper in your pool. It might not be in the water but it is deposited on the surface and can leach back into the water if your pH drops.
Good luck on fighting the stains!

[PopcornGirl]

Oh, wow. Ok, that makes sense. Guess I'll be going to buy a metal test kit.

I don't really trust my pool store completely, either. Although, I do not go to a national chain store (whose name I won't mention) that seems to be run by uneducated teenagers -- we do have one nearby, but I won't go there!
My store is a family-owned business that has been around for about 20 years and the owners (mid-50's couple) do all the testing themselves. But I still don't trust them implicitly because they are running a business and they profit from my *needing* more chemicals. That's why I joined this forum.

I think you have a excellent point & I will get that water tested right away!
BTW, it's now been nearly 36 hours with the Metal Out and there is NO change in the stain. DEFINITELY the wrong course of action...
Thanks!

[PopcornGirl]

Alright, I did a little *research* and read about a "vitamin C test" to see if ascorbic acid is what I need...
I took a handful of Vitamin C (chewable orange juice tablets) and put them in a white sock and secured it with a rubber band. Then I used a hammer to break the tablets down to a large gravel (not powder). I then tied this sock on to my pool brush and used the brush to hold the sock against the stain for 30 minutes.
There doesn't appear to be any difference in the stain!

Now, does that mean I do NOT need to use ascorbic acid or was that a total waste of my time (and my expensive Vit. C tablets)???
HELP! I don't want to spend any more money on this than I have to...

[waterbear]

I think the first step you should take is test the water for everything including metals so you will know what is going on. Also my understanding is that ascorbic acid is very pH dependant for it's use as a stain remover. I am not that familiar with it's use. I know several companies market it as a stain remover (reading a MSDS will usually tell you what is in the product). Perhaps the second step is to do a bit of internet searching and looking at the various products and what is in them and how they are used. Above all, DON"T GIVE UP! Like I said before I am not an expert on stains in pools but I know that there are several on this board! I'm just a guy with a little knowledge and a big mouth!

[vgg659]

I think we're neighbors.

I'm on Baton Rouge Water, use the same pool supply store, and we have the same problem. Sounds like water problems.

In the past, Parish Water (a.k.a. Baton Rouge Water) used local wells purchased from Capital Utilities to augment their water supply when necessary. These wells are notoriously high in iron; I know, because I used to be on one of them before becoming a Parish Water customer.

Anyway, back to your problem. I have the same stains, but I originally thought that it was tanic stains from live oak leaves and such. During Mardi Gras, we went to Colorado for a week. Upon returning, I had a large amount of live oak leaves in my pool. After cleaning it up, the stains appeared. So, I shocked at high levels, which is the prescribed method for getting rid of tanic stains. No luck.

So, I took a water sample to my friendly local pool supply store, but they were closed for the Easter holiday. I happen to have a quart of Metal Out, so I dumped it in. A day later, my stains have faded to the point of barely visable. I plan on another quart or two of Metal Out.

I have not had to top off my pool much, so I didn't think the iron came from the tap water. But, given your and my problem, and the common tap water source, I guess we have too much iron in our tap water and pool.

Good luck.