Pool Water Turned Brown After Adding Muratic Acid

Stains on the pool surfaces, pool equipment
or on the swimmers, or off-color swimming pool
water. Discolored but clear pool water.
Chris B

Pool Water Turned Brown After Adding Muratic Acid

Postby Chris B » Fri 01 Aug, 2008 16:00

Ok, long story short, I'm pissed off,,,, My pool water has turned shiat brown. Yes, I do have well water but the pool has been set up for over three weeks now. I ran the "iron out" crap through there that I got from the pool store which they suggested. Measure fine for metals. Water was crystal clear but the alkalinity was high, they told me to put a gallon of muratic acid in there and cycle it for twelve hours. Did that, the alkalinity came down to about 150 so they said add the second gallon, I did this, three hours later the pool water is shiat brown so now what???? I called the pool store (Watsons) and all of a sudden they don't know nothing, go fricking figure. PLEASE,,,, any help is greatly appreciated. :evil:


Guest

Re: Pool Water Turned Brown After Adding Muratic Acid

Postby Guest » Fri 01 Aug, 2008 17:00

How large is your pool. A gallon of muriatic acid at a time is quite a bit.

Brown water usually indicates iron in the water. I would use more of a sequestering agent.

Where are your chlorine levels, pH and TA right now?

Chris B wrote:Ok, long story short, I'm pissed off,,,, My pool water has turned shiat brown. Yes, I do have well water but the pool has been set up for over three weeks now. I ran the "iron out" crap through there that I got from the pool store which they suggested. Measure fine for metals. Water was crystal clear but the alkalinity was high, they told me to put a gallon of muratic acid in there and cycle it for twelve hours. Did that, the alkalinity came down to about 150 so they said add the second gallon, I did this, three hours later the pool water is shiat brown so now what???? I called the pool store (Watsons) and all of a sudden they don't know nothing, go fricking figure. PLEASE,,,, any help is greatly appreciated. :evil:
Chris B

Water turned brown after adding muratic acid

Postby Chris B » Fri 01 Aug, 2008 18:59

Well before I put the muratic acid in the cholorine was at 1.2, the PH was at 7.8 and the alkalinity was at 180. The guy at Watson's said put a gallon of muratic acid in and let it run through the filter for 12 hours. I did that and the water was still crystal clear. Watson's then said add the second gallon of muratic acid. Five to six hours later the water went from crystal clear to crap brown. I then called Watson's again here in Minnesota and I got the big "Duh" from them. They have "no idea why it turned brown" Called the Watson's in St.Louis and they were more helpful, they basically said what you said, that was far too much muratic acid to add at one time, should have been a quart every four hours. They then told me to add cholorine so thats what I have done but low and behold its still brown. The cholorine is up at 5 now, way high and the ph is at 8.8 but the alkalinity has come down to 148,,,,, whooooop eeee it's still brown crap. Don't know what to do as the local pool guy says add more iron remover,,,, I'm stumped and tired of paying all kinds of money for more and more chemicals.
Chris

Pool Size

Postby Chris » Fri 01 Aug, 2008 19:00

It is a 24ft round 54 inch wall pool 13,600 gallons
Guest

Re: Water turned brown after adding muratic acid

Postby Guest » Sat 02 Aug, 2008 00:13

I would use a sequestering agent to bind the iron in the water. What you want to avoid is staining from the metal in the water. Adding large doses of chemicals can cause that to happen.

As an example, I have a 30k gallon pool and I never add more than a quart of muriatic acid at a time.

Filter, get the sequestering agent in and monitor your chemical balance. Allow the chlorine level to come down naturally. If it disappears overnight you are probably dealing with algae also.

Are you filling the pool with well water?

Chris B wrote:Well before I put the muratic acid in the cholorine was at 1.2, the PH was at 7.8 and the alkalinity was at 180. The guy at Watson's said put a gallon of muratic acid in and let it run through the filter for 12 hours. I did that and the water was still crystal clear. Watson's then said add the second gallon of muratic acid. Five to six hours later the water went from crystal clear to crap brown. I then called Watson's again here in Minnesota and I got the big "Duh" from them. They have "no idea why it turned brown" Called the Watson's in St.Louis and they were more helpful, they basically said what you said, that was far too much muratic acid to add at one time, should have been a quart every four hours. They then told me to add cholorine so thats what I have done but low and behold its still brown. The cholorine is up at 5 now, way high and the ph is at 8.8 but the alkalinity has come down to 148,,,,, whooooop eeee it's still brown crap. Don't know what to do as the local pool guy says add more iron remover,,,, I'm stumped and tired of paying all kinds of money for more and more chemicals.
Chris B

Brown Pool Water

Postby Chris B » Sat 02 Aug, 2008 03:52

It's getting worse! Yes, I have well water. The pool has been up for just over three weeks now and had been crystal clear. I took a jar of water into Watsons and they tested it. They said the alkalinity 178 and the ph 7.8 were both high and had to come down. I was told to put a gallon of muriatic acid in, cycle it for twelve hours and then re-test it. I bought the tester they use (aquateck) and it still read up at 160, the water was still crystal clear. Watson's then instructed me to add the second gallon. 5 to 6 hours later is was brown. When I first filled the pool I ran "iron remover" for over twelve hours with no cholorine or nothing as instructed. Then I started running the cholorine. So today, just over three weeks now since the pool has been up I have this problem. Watsons here in MN has been no help now. I called the Watsons in St. Louis and they told me that I should have only been adding this muriatic acid a quart at a time and monitoring it every four hours. So that is really great I talked to an idiot right from the get go. The St. Louis Watsons told me to add cholorine because the cholorine level has since dropped to 0. The alkalinity is down to about 138 but the ph dropped to 6.7. I went to the store to get some "sodium based cholorine" that St.Louis Watsons suggested but the local pool store didn't have a "sodium based cholorine" the local pool store (A-Pro) said cholorine is cholorine and he told me to add a gallon since there was no cholorine present at all. Well now 9 hours later of course the cholorine is through the roof (9.0) and I still have brown water. I am REALLY REALLY worried and have no idea who to listen to now. My pump has been running none stop, I've been pulling the filter every couple of hours to clean it as it is brown as can be. I feel no one cares whos been helping me at Watsons and now A-pro. I'm really worried. I don't know what to do next.
Chris

Can I add more iron remover?

Postby Chris » Sat 02 Aug, 2008 03:56

Can I add more iron remover with all that cholorine in there???? I was already worried with all these chemicals in there before you mentioned it and now I'm even more worried. I heard it was good to add iron remover once the cholorine is in there and as I mentioned that is now through the roof and I'm worried about that.
Chris B

Latest readings

Postby Chris B » Sat 02 Aug, 2008 05:02

CL = 7.2
PH = 6.6
ALK = 126

Water is still brown, filter is pathetic brown


Prior to the water turning brown readings were
CL = 1,2
PH = 7.8
ALK = 178

Chemicals that have been added since
Muriatic Acid = 2 Gallons
CL= 1 gallon(liquid)
GLB (Sequa-Sol) = 16oz

Still brown water
Guest

Re: Latest readings

Postby Guest » Sat 02 Aug, 2008 06:30

Yes you can add more sequestering agent although it may not be needed.

What needs to be done right away is to gently raise the pH. By gently I mean small amounts of chemical, retest, adjust as needed. I would get the pH to about 7.2.

To raise pH you can use borax (20 mule team laundry additive for supermaket). If you already have pH up, then you can use that. You want to keep the iron in solution so a lower pH like 7.2 would be good.

The alk (TA) is fine for now and so is the chlorine. Adding the chlorine (especially in large doses) is usually what brings about the brown water.

The sodium based chlorine you mention is just liquid chlorine you get at a pool store or Home Depot type store. Also, household bleach (unscented) is also sodium based chlorine. Same as the stuff from the pool store but in a lower strength.

To get the brown out you filter, filter, filter (cleaning the filter over and over). The other way is to drain off some of your water and refill. The trouble with that is you're using the same well water that has iron in it.

One thing you might try is turning off your filtering system for the night. This should allow some of the mess to settle out. Slowly vacuum to waste to remove it.

The key, should you ever have clear water again, is to not add too much chlorine too quickly. The chlorine reacts with iron and bingo, brown water again.



Chris B wrote:CL = 7.2
PH = 6.6
ALK = 126

Water is still brown, filter is pathetic brown


Prior to the water turning brown readings were
CL = 1,2
PH = 7.8
ALK = 178

Chemicals that have been added since
Muriatic Acid = 2 Gallons
CL= 1 gallon(liquid)
GLB (Sequa-Sol) = 16oz

Still brown water
Chris B

Brown Water

Postby Chris B » Sat 02 Aug, 2008 07:40

The key, should you ever have clear water again, is to not add too much chlorine too quickly. The chlorine reacts with iron and bingo, brown water again.


I did not add the gallon of chlorine until after the water had turned brown. My chlorine level was at 1.2, ph was 7.8 and alk was 178 thats when the Watsons clown said to add all the muriatic acid. Thats when the water turned brown. I added the remaining 16oz of the sequestering agent this morning. It seems like the water lightened up a bit over night but not much.
How much is too much when it comes to adding additional sequestering agents? how long should I wait now since I added the second 16oz of the sequestering agent at about 6:00a.m. this morning?
Thanks for continuing to write back by the way, I really appreciate your time and help.
Guest

Re: Brown Water

Postby Guest » Sat 02 Aug, 2008 18:54

I didn't explain the chlorine comment very well. Chlorine oxidizes the iron causing the brown coloring. Although you didn't add chlorine you did add a large amount of muriatic acid.

The muriatic acid lowered the pH into a range where small amounts of chlorine is too much. How much of the chlorine in the water that is in it's active state is dependent on the pH.

For example, at a pH of 8 only 20% of the chlorine in the water is in the "killing form" as it is often called. At a pH of around 6.5, 100 % of the chlorine is in the killing form. When they told you to add a gallon of muriatic it lowered your pH enough to cause your chlorine to react to the iron.

One of the reasons I suggested raising your pH right away was to prevent your chlorine level from continuing to react with the iron. The other reason is that a pH below 7 is acidic and will react with any metal in your system especially the pool heater if you have one.

I believe I suggested raising to 7.2. Having thought about it I would continue to raise it to about 7.8. Once the reaction between chlorine and iron stops the pool will clear sooner.

On a side note, you already have iron in the water so the last thing you need is to add algaecides containing metals (copper).

I was hoping someone else with experience with brown water would chime in here. I've never dealt with turning a brown pool clear but I do understand the chemistry that brings it on.

Follow the directions on the sequestering agent you used. Small weekly doses are often called for.



Chris B wrote:I did not add the gallon of chlorine until after the water had turned brown. My chlorine level was at 1.2, ph was 7.8 and alk was 178 thats when the Watsons clown said to add all the muriatic acid. Thats when the water turned brown. I added the remaining 16oz of the sequestering agent this morning. It seems like the water lightened up a bit over night but not much.
How much is too much when it comes to adding additional sequestering agents? how long should I wait now since I added the second 16oz of the sequestering agent at about 6:00a.m. this morning?
Thanks for continuing to write back by the way, I really appreciate your time and help.
Chris B

Water Clearing Up

Postby Chris B » Sun 03 Aug, 2008 12:53

The water has finally for the most part cleared up :D After adding the gallon of chlorine(liquid), using the GLB Sequa-Sol and washing out the filter every couple of hours the pool has drastically improved. There is still a greenish hue to it but leap years ahead of where it was. I'll continue to add small amounts of the Sequa-Sol sequestering agent per yours and the A-Pro pool store guys suggestion. Thanks so much for all your time and help, I appreciate it so much you continuing to come back and update your helpful replies.

Chris
Guest

Re: Water Clearing Up

Postby Guest » Sun 03 Aug, 2008 18:11

My pleasure. Enjoy your pool and good luck.

Tim

Chris B wrote:The water has finally for the most part cleared up :D After adding the gallon of chlorine(liquid), using the GLB Sequa-Sol and washing out the filter every couple of hours the pool has drastically improved. There is still a greenish hue to it but leap years ahead of where it was. I'll continue to add small amounts of the Sequa-Sol sequestering agent per yours and the A-Pro pool store guys suggestion. Thanks so much for all your time and help, I appreciate it so much you continuing to come back and update your helpful replies.

Chris
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2381
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

Re: Brown Water

Postby chem geek » Fri 27 Feb, 2009 17:16

Pool User wrote:The muriatic acid lowered the pH into a range where small amounts of chlorine is too much. How much of the chlorine in the water that is in it's active state is dependent on the pH.

For example, at a pH of 8 only 20% of the chlorine in the water is in the "killing form" as it is often called. At a pH of around 6.5, 100 % of the chlorine is in the killing form. When they told you to add a gallon of muriatic it lowered your pH enough to cause your chlorine to react to the iron.

Though this is an older thread that got revived by a garbage/spam post, I thought I'd correct a misconception about active chlorine concentration vs. pH. Though the above quoted statements are true with regards to the active form of chlorine, hypochlorous acid, when there is no Cyanuric Acid (CYA) in the water (though at a pH of 6.5 it's 90% in the killing form, not 100%), this is not true when CYA is present. With 30 ppm CYA in the water, at a pH of 8.0, 1.1% of the chlorine is in the killing form while at a pH of 6.5, 3.1% of the chlorine is in the killing form. A comparison of the true graphs without and with CYA are shown in this post. Basically, the CYA helps to buffer chlorine against changes in pH, though it mostly just binds with most of the chlorine so much less is in the active form. This all comes from the science of chlorine and CYA known since at least 1974 as described in the paper in this link.

Nevertheless, this really doesn't matter with regard to oxidation of iron since the amount of active chlorine only determines the rate of the oxidation reaction, not the capacity of whether it gets to completion which is determined by the Free Chlorine (FC) amount (assuming there was more solid iron particles than chlorine). The oxidation of iron is more rate limited by pH than by chlorine concentration so the fact that a smaller proportion of the chlorine is active isn't particularly relevant. It's the low pH itself that is more the cause of being able to oxidize solid iron particles into iron ions. The chlorine helps, but the low pH is the bigger factor. In any event, using a metal sequestrant is the correct prescription, along with filtration to remove bigger particles. I'm glad the problem got resolved and that Tim was able to help -- that's what is most important.

Richard
Daniel Martinez

Pool Water Turned Brown After Adding Shocker

Postby Daniel Martinez » Tue 16 Jun, 2009 10:50

The water in the pool was somewhat clear but it had a greenish tint to it added some shocker to the water
and the pool water turned to a brown color i am in need of some help can anyone help me with this problem
the water after i put the shocker in it was nice and clear and in about one hour it started to change to a brown tint and then it turned to a darker brown

please help

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