At My Wit's End With Stains

[bwilliamson]

Hello all. I'm new to the forum and some help would be greatly appreciated. When I opened my pool this year I noticed stains everywhere. I tried a couple of products, and Jack's Magic Solution No. 1 supplemented with their "Blue Stuff" worked excellent. I followed the instructions my local pool pro gave me and waited a few days before adding any chlorine. Once I did I noticed the stains came back. This went on for a couple of weeks. Finally I go back to my pool pro and they ran a water test and called jack's magic. Jack's then tells them the Cyanuric Acid is too high (approx. 180 ppm) and the metals couldn't filter out of the water after they lifted off of the liner and steps. They recommended "diluting" the pool by draining and refiling. I've done that once and the cya is down to 135 ppm. My pool pro is now saying I need to drain and refill two more times to get the cya down before I do another Jack's treatment.

I'm trying to see if anyone would recommend another product or another solution that doesn't involve me dumping over 20,000 more gallons of water and going through a couple more hundred dollars in expenses (already spent around $400 on this problem). Any help would be greatly appreciated. Thanks!

 

[tim5055]

I'm sorry to say, that the stains are. probably the least of your problems. What pool stores (you call the, pros, but they are far from it) fail to tell you is that all the tabs and shock they sell you contain CYA. The more CYA I the water the more other problems you have like chlorine not sanitizing the water the way it should.

Unless you are running a salt water chlorine generator you really need to get that CYA down to about 50. With a SWCG you can stretch that to 70.

You really need to do a water exchange, but I would stay away from the "Pro"

We have several great articles in Pool School, but I would start with these:
Pool School - ABCs of Pool Water Chemistry
Pool School - How to Chlorinate Your Pool

 

[pabeader]

The "pros" are here. Not in a store.

 

[bwilliamson]

I'm sorry to say, that the stains are. probably the least of your problems. What pool stores (you call the, pros, but they are far from it) fail to tell you is that all the tabs and shock they sell you contain CYA. The more CYA I the water the more other problems you have like chlorine not sanitizing the water the way it should.

Unless you are running a salt water chlorine generator you really need to get that CYA down to about 50. With a SWCG you can stretch that to 70.

You really need to do a water exchange, but I would stay away from the "Pro"

We have several great articles in Pool School, but I would start with these:
Pool School - ABCs of Pool Water Chemistry
Pool School - How to Chlorinate Your Pool

so you would recommend using regular bleach in lieu of chlorine tabs and shock ?

 

[pabeader]

Yes!! Only use pucks if you need to add CYA or for vacation.

 

[tim5055]

Yes, the "secret" pool stores don't want you to know is that all forms of chlorine are the same chemical. The differences are in concentration and any added "stuff" it carries along.

solid forms of chlorine give you either CYA or calcium. Both of which are bad for your pool at high levels.

The TFP website believes in accurate testing and only adding to your what it needs, when it needs it. Tabs have their place when your CYA is low and you will be away and not,able to,add chlorine yourself. The continual usage of tabs just drives the CYA level through the roof.

The stores don't tell you these things. My bad voice says its so they can sell you more stuff later. My good voice says they just don't know any better.

 

[bwilliamson]

So just to make sure I understand:

1) drain and refill pool until I get CYA down to 50 ppm

2) treat with stain remover (jacks magic?)

3) when I begin chlorinating again use household bleach

Is that correct ?

 

[tim5055]

Well, I'll add another dimension to your issue. The stains are caused by metals. How the metals got in the water are a different issue which should be dealt with later. The most common source is algecide the "Pros" sell.

As you are about to dump most of your water to get the CYA down you could do an absorbic acid treatment just before you dump the water. The AA treatment will remove the stains from the surface and place them back in solution in the water. Then, when the water goes the metals go with it. Check out this article:

Ascorbic Treatment to rid Pool of metal stains

Just remember, when you get to the part in the treatment to add the sequesterant, you dump water there.

But, with no AA treatment, the answer to the three questions is yes to all.

 

[bwilliamson]

Could it be from the screws and casing for the light? If so should I swap those out too?

 

[tim5055]

No, the most common sources are copper based algicides or running a pool with the pH out of range and letting it degrade copper pipes in a heater. Another source would be high. Teals in the fill water, usually from a well.

 

[bwilliamson]

Ok guys really appreciate the help thus far. I only have one more question. Because I have a vinyl liner, I really don't want to drain the pool all the way. If I drain almost all of it and dump the water with the metals in it, do I run the risk of re-introducing the stains with the small amount of water I will salvage ?

 

[Swampwoman]

Welcome to TFP! Are you on well water, or had you used algaecide s with copper?

You need do do the partial drain either way to get your CYA down. It will dilute the metals, but its hard to say how much. You will later sequester the metals by adding either Metal Magic or Jack's Magic, and maintaining it through the season.

Either way, you are correct that care should be taken with vinyl, leaving at least a foot in the shallow end. If you need to dilute more, you can do a second partial drain.

If you're NOT on well and want to avoid needing metal sequestrants you cold choose to aim for an ultimate 100% drain in partial steps.

To avoid metal staining in general, keep your ph on the lower end of he scale, around 7.2. You do have one of the recommended test kis, right? You'll need to be able to test properly to follow TFP methods.
(TFT100 or Taylor K2006 specifically, both avail at http://www.tfttestkits.net )

Avoid shocking/slamming (via never letting te FC drop blew your CYA value to get algae in the first place) because the oxidization of the metals can also cause stains.

However, if you DO need to Slam/shock, don't add metal sequestrant during the process. They work best at low chlorine levels, and you shouldn't shock/slam for a full week after you've used them.

Hope that helps!

 

[Task]

Ok guys really appreciate the help thus far. I only have one more question. Because I have a vinyl liner, I really don't want to drain the pool all the way. If I drain almost all of it and dump the water with the metals in it, do I run the risk of re-introducing the stains with the small amount of water I will salvage ?

Definitely do not drain all the way. I'd say you should leave at least 10-12 inches of water in the shallow end of your pool. If you drain all the water from your pool, you could risk having your liner shift or possibly rip. If you have a shallow side and a deep side in your pool, once you drain all the water down below the shallow side, the weight of the water in the deep side could pull the liner. Unfortunately, you'll have to drain until you have about a foot or so in your shallow end and then refill and repeat.

While refilling and repeating, you'll be removing CYA and the metals from the pool. You need to consider your fill source also. Are you filling from a well? If so, you should test that well water as it could contain metals and you'll only be adding the metals back into your pool.

 

[bwilliamson]

Not on well water - the metals must have come from algecides.