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BarryY
03-29-2006, 01:04 PM
I get brown stains in my fiberglass pool all the time. I can effectively remove them with oxalic acid, but it always turns the water cloudy for about 3 days. Jack's Magic Blue Stuff also works, but it costs me a fortune at over $20 a bottle. I heard somewhere about using ascorbic acid. Where can I get it in bulk? Is it expensive? Will it turn the water cloudy? Will it get the stain out?

waterbear
03-29-2006, 04:10 PM
Iron is your problem, Oxaylic acid is a known remedy for rust (oxidized iron) stains! It is toxic, however. Phosphonic acids are also effective and are the active ingredient in most of the "metal removers" I have seen. You can learn a lot about a product by going to the manufacturer's website and reading the MSDS for it. Ascorbic acid works (if I am not mistaken) by acting as a reducing agent just like Oxaylic and Phosphonic acids. These will also lower your pH and their effectiveness is dependant on pH so read your directions!

cajunfla
03-29-2006, 09:05 PM
Have you tried the new Mr Clean Magic Eraser? My fiberglass pool gets a dirt ring around it. Not all the sod has been installed yet. Mr Clean works wonders.

msehome
04-01-2006, 10:13 PM
http://www.msm-msm.com/store/agora.cgi?cart_id=%%cart_id%%&product=Vitamins&user4=Ascorbic%20Acid

I have a 35,000 gal fiberglass pool and it stains all the time. Dont have a heater, and no iron pipes. It takes about a pound to a pound and a half of ascorbic acid to make the pool beautiful again. This is the cheapest I've found for it. $45.00 for 5 lbs. and if you buy over $100.00 at a time its free shipping. Heres a pic of my fiberglass pool.

http://i6.photobucket.com/albums/y222/msehome/Christmas2005050.jpg
Good Luck

BarryY
04-01-2006, 11:01 PM
Thanks, msehome, I'll give it a try. Does it turn your water cloudy when you add it?

msehome
04-02-2006, 11:07 PM
Not at all, its amazing to watch the stain dissappear right before your eyes. And the water stays clear.

Good Luck

BarryY
04-03-2006, 03:55 PM
OK, I just ordered some. Can't wait to try it, thanks.

mbar
04-08-2006, 10:00 AM
I also have a fiberglass pool, and I have learned to deal with the stains pretty effectively. When I get stains I use ascorbic acid, and a metal free product. The cloudy water is the metal free agent combining with the metal that has come back into solution. If you have a lot of metal in solution and the water is cloudy, you should not start to bring up your chlorine until the water is cleared - you can put a chlorine puck in the basket so the metals will stain the filter. You have to try and keep the ph around 7.2, not higher - it is hard to keep the ph there, because the stain treatment brings down the ph, plus the puck in the skimmer will add to lower ph. Be sure to keep your filter running 24/7 - once the water is clear, you can start to bring up the chlorine. I use regular bleach, and I don't run high chlorine levels - it isn't necessary especially if you keep your cya under 50. In my opinion, fiberglass pools tend to stain, I now treat it heavily at the beginning of the season with a metal free product, and keep the filter running 24/7 when I have high chlorine levels. All water and pools are different - you will have to experiment with yours to see where you need to keep your chlorine & ph to keep the stains away. Don't worry so much - if it stains, it can be taken care of!

Arizonaoldman
04-12-2006, 10:57 PM
I too have a 21,000 gallon fiberglass pool and a salt to chlorine generator. We have extreamly hard water and I just had my generating cell replaced after only two years. (free of course) Last year I began to have brownish 'build-up" at, or above the water line only in two areas (both wind driven areas) I had been using a 'Bio Guard" product "Off the Wall" on a weekly basis until late last fall. This year the stains are quite noticeable and no amount of "Off the Wall" and/or elbow grease seems sufficient. Do you think the Ascorbic Acid trick will work for me? Remember that most of the stain is above the water line. Will scrubbing with the ascorbic acid do the trick.

By the way I life in north western Arizona.

Ralph

mbar
04-12-2006, 11:24 PM
If the stain is above the water line, then I don't know how it would be from iron falling out of the water. You can tell if it is mineral by rubbing a vitamin c tablet on the stain. If it takes it off, then ascorbic acid would work. You wouldn't have to scrub with ascorbic acid - just letting it touch the stain will make it disappear. Let me know if the vitamin C tablet (you can put a couple in a sock, soak the sock and rub it on the stain) works. If it is stain from leaves, they come off after chlorine is on them for a while. I have also had good luck with cleaning the water line with magic erasers. Hope this helps

Arizonaoldman
04-13-2006, 08:10 PM
I tried the Vitamin C Tablet today. Got it wet then used it directly on the stain.
No luck whatsoever. Tried Mr. Clean Magic Eraser yesterday, still no luck. I refuse to give up.

Ralph

mbar
04-14-2006, 09:08 AM
I read somewhere that you can put a little ph reducer in a sock, wet it, and rub it on the stain - if it is mineral it should take the stain off. You probably would want to wear gloves when doing this. Let me know if this helps. I wouldn't give up either!

DavidD
04-14-2006, 04:57 PM
You are in good hands Ralph. Marie (mbar) helped me allot a couple of years ago and turned me on to the Vitamin C. I owe her much gratitude. I too have a Fiberglass pool and seam to have to treat my pool a couple of times each season. On another thread, waterbear has brought to light a yet unsubstantiated claim by a company (Water Tech I believe?) that a lack of calcium could cause problems in vinyl/fiberglass pools. No one is sure if this is true yet and I personally have my doubts but just for the sake of "research", would you post your numbers? Mine are as follows:

FC 3
CC 0
TC 0
PH 7.5
ALK 80
CH 60
CYA <30
Temp 84
16,000 gallon I/G Fiberglass

I currently have stains. My stains generally appear as grey lines running from one side of the pool to the other. They even appear as orange/yellow sometimes in certain light. The pool has been open for a couple of weeks now and the stains have progressively gotten worse. The last treatment was in August '05 and I'll be giving it the ascorbic treatment after the weekend. I'm trying to keep a log to try to figure out what is causing these stains and would like to compare others numbers when staining has occurred. I use a water filter (cheap RV type) when filling and have had my water tested for metals and there are no traces of Iron or Copper. Notice My Alk and CH are low? I'll be working on those after the treatment next week. I usually keep ALK between 90 & 100 and have never worried about CH but it has never been this low. I did do a partial drain when opening to get the CYA down and I guess the filter is working since no calcium seems to be added. Thanks in advance for your help.

Dave

mbar
04-14-2006, 06:55 PM
Hi Dave, I am still trying to figure out what causes the stains. Your numbers seem perfect to me. Have you added any sequestering agent since opening? I also read somewhere that "Fiberglass has a negative electrical charge and can attract positively charged metallic ions, causing the development of a stain. The periodic addition of a metal treatment should help negate this effect and help keep pool stain free. " I don't know if any of this is true - but it would seem to be a reason that the fiberglass stains so easily. I haven't opened my pool yet this year, probably in about 3 weeks. I plan to add sequasol first before anything, then test all the chems and bring up the chlorine slowly. I think the most important is to have the sequestering agent in the water in a large quantity before doing anything at all, including a stain treatment. Maybe between all of us we can figure out why we get the stains - we know how to get rid of them, but it would be nice to not ever get them!

waterbear
04-14-2006, 06:59 PM
I also read somewhere that "Fiberglass has a negative electrical charge and can attract positively charged metallic ions, causing the development of a stain. The periodic addition of a metal treatment should help negate this effect and help keep pool stain free. " I don't know if any of this is true - but it would seem to be a reason that the fiberglass stains so easily.
Can you substantiate this in any way? I would be interested in knowing where this statement came from.

mbar
04-14-2006, 08:00 PM
I was googleing stains on pools, and I came accross this website:

http://www.askalanaquestion.com/pool_stain_problems-page_2.htm

There is a whole archive from "Ask Alan" on pool stains. I am going to search some more and see what I can find out about it. If anyone else has any information it would be greatly appreciated!!

DavidD
04-17-2006, 09:14 AM
Marie,
I have not added a sequestering agent yet but had planned to after I did the ascorbic acid treatment. I would usually then backwash/replace DE and add more sequestering agent after all is said and done. Maybe I'll try just the sequestering agent first and see what happens. I'll let you know.
Now let me clarify, these stains are not that noticeable in full sun but usually in low light, such as evening, and I notice them more than others (maybe OCD?).:rolleyes:
One observation I have made so far is that the stains appear to be occurring where the gel coat was sprayed in intervals. This is the only explanation for the almost perfectly straight lines that divide my pool in to 3 equal parts. I know that when gel coat is sprayed, you can usually only spray up to about a gallon or so at a time due to "kick off " times (the time in which the gel coat will start to cure). So it appears that where one part overlapped the other, staining is more prone. Makes we wonder if maybe there are slight indentions or something in these areas that collect the stains. After all, fiberglass/gel coat/resin is not absorbent so the stains occur at these locations for some reason.:confused:
Either way, It really isn't that big of a deal and if I had to do it all over, I'd still choose the same pool, stains and all!

mbar
04-17-2006, 10:24 AM
Me too Dave! I love the fiberglass, stains and all. I noticed the same thing - my stains always seem to appear in the same places. My opinion is to put the sequestering agent in first, so whatever metals are still in solution will be filtered out. Then again when you do a stain treatment, so that the metals will bind to the sequestering agent as soon as they go into solution. My plan this year when I open is to put in the sequestering agent, slowly raise my chlorine, and balance the pool. I plan to run low cya (about40) so that I don't have to keep my chlorine very high. I also plan to keep my ph around no higher than 7.4. What I think, and it is only what I think so far, is that when the ph is low, the chlorine is more potent, which can let any metal in the water fall out onto the surface of the pool when the filter is off and the water isn't moving. But on the other hand low ph keeps the pool on the acidic side, which keeps the stains in solution, making the sequestering agent able to get rid of the stains before they fall onto the surface of the pool. This is why it is so confusing. So in my opinion lower ph with lower chlorine levels should keep the pool less suseptable to stains. I really don't know yet!! I am still in experimental stage - every time I think I know how and why the stain comes, something happens to destroy my theory. Anyway this is my plan for this year, I will let you know how it goes. I think keeping the filter running for 24/7 for the first couple of weeks after adding the sequestering agent is the most impotant thing when I first open the pool. I have never had stains when the pool is first opened, it seems it happens when I shock the pool on opening. That's why this year I plan to put in the sequestering agent first before taking the water up to shock levels. Keep me informed on what you learn too, maybe we can figure this out!

wsmith002
05-22-2006, 04:17 PM
Every year it is the same thing for us. Once the chlorine level goes up, light brown stains on the floor, steps and sides begin to appear. StainFree (Vitamin C) will take then up for a couple of days then back them come. Pool builder just says it's something I'm doing. The only place not stained is the seems on the bottom.

cajunfla
06-02-2006, 05:10 PM
OK, I guess I will be joining this thread. I have the dreaded brownish stain all over the fiberglass below the waterline. Did a partial drain today, mostly to get rid of HIGH CYA. Tried scotchbrite pads, even pressure washer. NO JOY !

Going to try the Stain Remover (ascorbic acid) from Leslie's. The lable says I must use with Metal Free to pevent re-occurance. Buying that brand because I don't want to wait for a shipment. I will add to pool after re-fill is complete, and post results of stain removal tomorrow.

Jeff

mbar
06-04-2006, 11:40 AM
Here are some observations that I have noticed over the years with stains. Make sure you add enough sequestering agent. It won't hurt anything if you put more in than you need, but it will leave some metals free to stain if you don't. Keep your ph on the low side - I like to keep mine between 7.2 - 7.4, no higher. Keep you chlorine consistant - don't let it drop down to where you will have to shock. High chlorine levels will let any metals that are free in your pool to precipitate out and land on the pool. When you start to see the stain forming, add more sequestering agent and bring your ph back down to 7.0 - 7.2., and keep the filter running 24/7. It seems that the stain will lift with the sequestering agent and low ph if it hasn't become too embedded. If the stain is localized, put a little ascorbic acid in a stocking and rub it on the stain - this way you don't have to do the whole treatment.

cajunfla
06-05-2006, 09:30 AM
Leslie's Stain Remover (ascorbic acid) and Metal Free worked great !! Stain disappeared in minutes.

Jeff

charlescab
05-20-2010, 06:12 PM
I used to use leslies all the time and it does work well but gets expensive, as I have to remove stain weekly. Every time I raise the chlorine it comes back.

I used to do this and it took about 3 days to do it (leslie's method)
1) Lower the chlorine (about $10 for the bottle)
2) Use metal free (I think $20)
3) run for a couple days
4) Back flush
5) Destain using Leslies Ascorbix acid ($40 for 2 pounds)
6) Raise the chlorine

But I have found that the ascorbic acid is a contact agent, and a cheaper way to do this is
1) Order ascorbic acid from MSM MSM (Half the price 12.50 a pound as opposed to leslies $20 for a pound)
http://www.msm-msm.com/faq.html
2) Turn off the pump for 1 hour
3) Drizzle very small amounts of the ascorbic acid around the edge of the pool (about .75 pounds max for a 15000 gal pool)
4) Let ascorbic acid float down the sides of the pool
5) Let the pool sit for 4 hours, then turn the pump on. The next morning its perfect.



I have had this problem for 3 years and at the beginning of every pool season I have spent countless dollars lowering the chlorine, using metal free, and using ascorbic acid only to have it come back even when the tests at the pool store say there is no metal in my pool.

The method above costs me about $10.00 a week