Metal in pool

[doriec]

I recently added 2 qts. of metal out to my 27,000 gal. pool. It cleared up the stains beautifully. Then the water clouded up and turned green so I shocked the pool. The ph fell to 6.8, the water turned green, and it took 27 gal of bleach before the FC remained steady. The ph fell to very low levels. After reading the posts, I can see my mistakes. My questions are these:
1. I need to pour in more metal out after lowering the ph and FC levels. How much more can I add? Keep in mind that I already added 2 qts before my problems occurred.
2. Does the filter expel the old metal out and sequestered metals when I backwash? Or do they stay suspended in the water as the filters returns the water to the pool?
3. Do I always have to keep my water's ph low to keep the metals from "dropping" out?
4. Will the metals "drop" out again whenever if I have to shock the pool to get rid of CC?
I have a salt pool. I fill with 1/2 well water (with lots of iron, I am sure) and I/2 with softened water because of hard well water.
My FC is 5
CC 0
ph 7.4
TA 150
hardness 250
I use bleach to shock, borax to raise ph, and acid to lower the ph.
Thanks for your help.
Dorie

[aylad]

I'm not the metals expert around here, but I can tell you that high pH and high Chlorine are going to cause the metals to start staining. You do need to keep the pH fairly low, but if it's a vinyl pool you don't want it to be below 7.0, because that's TOO low and can cause damage to the liner. If you need to shock the pool, watch it as the chlorine rises, and if you start seeing discoloration, add the metal out then.

I'm sorry I don't know how much to add or the answer to your other questions, but Marie (Mbar-- the resident metals expert other than Pooldoc) should be by soon and can help you further. IN the meantime, I encourage you to read through the other posts in the metals forum, and particularly the stickies, because you'll probably find some of the information you need to understand metals in there.

Welcome back to the forum!!

Janet

[doriec]

Thanks, Janet. It is nice to be back.
I forgot to mention that when I used metal out last time, aside from the cloudy pool, algae, and screwy chemical levels, my CYA level fell to 0. Why is that?
I am going to try the metal out again. This time I am going to be sure that I have low ph and FC levels before I add it. I hope someone out there can tell me if sequestering these metals will the filter to get rid of them. If not, it will be a game to keep the chemicals perfect to avoid the staining again.
Dorie

[aylad]

It's always going to be a game to keep the chems right. The metal sequestrants hold the iron in suspension in the water, but they don't actually remove them. There is a thread started by a new user, labdi01 where she talks about some sort of filter she made that actually removed the iron from her water. It apparently worked for her, but I don't have enough experience with it to know whether to recommend it or not. You can read through it at http://www.poolforum.com/pf2/showthread.php?t=9706 and it might give you some insight. Also, read through Pooldoc's post (#22) at this thread http://www.poolforum.com/pf2/showthr...?t=9660&page=3 and see if it helps.

Janet

[doriec]

Janet,
I read the last post you mentioned--very good. It answered some of my questions. Apparently, sequestered metals will filter out. That is good news. I still don't understand why the metal out drops the ph and eats up chlorine. Maybe someone can help with that one.
Thanks,
Doris

[doriec]

I am still having problems with staining. This is what I have been doing to correct the problem.

I lowered my ph to 7.2, allowed the chlorine to drop to .5, and then poured in the specified dose of metal out. The stains dissappeared almost immediately. For two days I ran the filter and backwashed each day. Then I allowed the chlorine level from the salt generator to rise to 1.5. and the ph to 7.4. Within hours, the stains came back. I lowered the ph and chlorine again, and the stains disappeared again. I am now running the pool and backwashing again. How long will this process take before the stains stay away? My pool numbers are good, except for the alkalinity which is 135. I am trying to get that down through lowering the ph and aeration.
Thanks for helping me.
Dorie

[waterbear]

Janet,
I read the last post you mentioned--very good. It answered some of my questions. Apparently, sequestered metals will filter out. That is good news. I still don't understand why the metal out drops the ph and eats up chlorine. Maybe someone can help with that one.
Thanks,
Doris

No, sequestered metals do not filter out. They are dissolved in the water and in an ionic form. Being sequestered means that they are not chemically reactive so they won't be oxidized and either color the water, deposit as stain, or precipitate out. Remember, the definition of sequester is to 'set apart' or 'put into seclusion'. Metals that have PRECIPITATED out of solution are filterable but they usually just redeposit on the pool as stain again.
If you are referring to my post about chitosan, remember I said that I do not know how effective it is, just that it has been documented that it can combine with metal ions and then filter them out. I do not believe it is a very effective process or someone would have already marketed it as a metal remover.

[mbar]

When I am dealing with staining I never lower the chlorine when putting in a sequestering agent. One of the reasons the stains are disappearing is because the chlorine level is so low You have to get the pool to a level where you can maintain a sanitized pool and keep the metals sequestered. You just don't have enough sequestering agent in the water. The problem is that chlorine eats the sequestering agent, which makes the chlorine levels go low, which can lead to algae, which leads to needing to shock, which leads to more stains That is one of the reasons that I don't let the chlorine drop to add the stain treat. You can add some algaecide, which will help when the chlorine does go down. Here is what I would do, Get your chlorine where you want it by slowly adding it - keeping the ph low. Add more sequestering agent, if you see the stain start to come back, add more agent. Keep checking the chlorine and add it slowly to keep it at the level you need for your cya. It can take a while to get it right, but once you do, you just need to add the maintenance dose of the sequestering agent on a weekly basis. Remember you want the water sanitized first - that is the most important, this way you can swim - you can swim with stains, but not with water that has aglae

Waterbear is right, you can't really filter out the metals, the only thing you can do is to keep them sequestered, or get them to stain on the filter, as PoolDoc explains in his post. Hope this helps, and feel free to ask any other questions you may have.

[newpoolgirl]

I don't mean to barge in, but what they are telling you is correct. if your levels go out of wack. you will be back to square 1. I was having this issue since may. Tried metal out, but what my pool store wasn't telling me was to keep my levels balanced. I did find a product to clear my brown water since i have a small cartridge filter with my 5,000gal intex pool that doesn't do much. It's called pool stain treat. it's a sequestrant and chelator. Don't ask me what that means, but after 2 days of using this my water cleared,and the cartridge filter actually caught all the brown(washed it out 4 times). I bought this product on my own as a last resort before I took down the pool. Called the company that makes it(united chemical corp.) And just like the above posts the company told me that even with this, if my levels are off, bam, back to brown water. They said for this chemical to work you levels have to be balanced. This site is the best one that I have found out there. Thank you and keep up the good work.

[waterbear]

Pool stain treat is just oxalic acid. It works exactly the same as ascorbic acid but is more toxic. (Citric acid also works the same.) You are just lucky the stain reformed in your filter and not in the pool. A sequestrant is still needed.

United chemical sell a lot of different products and makes a lot of claims for them. When you realize that the majority of their products are just soduim bromide (Pool stain Treat and the stain spotting bags being an exception since they are oxalic acid) and you look at the nonsense they call the Hamilton Index that they used to promote (and still do with their water balance recommendations) then you have to look at their claims for the products with a grain of salt.

I am not saying these products do not work, in fact they do (some better than others). It's just the marketing hype does not quite agree with the reality of what is really happening.