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Thread: Manganese stains?

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    Manganese stains?

    I am a new pool owner (2 years, see details below). First year was fine. This year, gray blotchy stains have appeared esp at deep end but apparent throughout pool.
    Water tested neg for copper and iron; have been adding Blue Stuff every week.

    Stain expert recommended by the pool company diagnosed 2 problems: (1) manganese stains;
    (2) "improper startup" leading to plaster not hydrating properly (I don't know what that means). Stain expert wants to do a 3-week treatment that he says will fix everything without draining the pool.

    My questions:
    If I have manganese in my water, how would I know?
    Is there an additive that chelates manganese?
    What did I do wrong to cause "improper startup"?
    And, does this proposed treatment make sense?
    Location: Media, PA (Philadelphia suburb).
    In-ground, 13,000 gallon pool, plaster, built 2008-9.
    Pump Whisper-flow 60 gpm DE filter
    Spa: 2013 Hot Springs/salt generator

  2. Back To Top    #2
    Guest

    Re: Manganese stains?

    First thing I would do is stop putting "Blue Stuff" in your pool. Second, could you post a full set of numbers so we can get a better feel for your pool water. I would hold off on paying anybody to fix it at this point. It might be a simple fix that you can do.

  3. Back To Top    #3
    solarboy's Avatar
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    Re: Manganese stains?

    Manganese=Black. Not sure how to get rid.
    Self built 5500 gallon bare concrete (temporarily) pool with limestone coping, Pentair Swimmey 1/2 HP pump, Triton sand filter with DE, Simpool peristaltic muriatic acid pump with pH sensor and Monarch SWG. Home made solar heater with Pentair Compool control panel and 3 way valve. 1 skimmer, 1 main drain, 2 returns, 2" plumbing, Hayward auto fill valve.

  4. Back To Top    #4

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    Re: Manganese stains?

    I believe that manganese stains should lift from the plaster with ascorbic acid much the same as any other metal stains would. Scrape the area with a vitamin C tablet and see if that helps. If it lifts the stain, you know it's metal.

  5. Back To Top    #5

    Re: Manganese stains?

    Thanks for the responses on the possible manganese stains.

    Sal: the water testing at the time the stains were becoming quite noticeable in the deep end were as follows:
    FC 3.4 TC 3.6 pH 7.5 Hardness 210 Alk 60 Cyanuric 105 Copper 0 Iron 0
    The low hardness and alkalinity were corrected. The pool has since been shocked.

    257WbyMag: the vitamin C test is negative. No effect of rubbing a chewable tablet on the stain.

    Can I test for manganese on my own?
    And, Sal: what's wrong with Jack's Blue if I might ask?
    Location: Media, PA (Philadelphia suburb).
    In-ground, 13,000 gallon pool, plaster, built 2008-9.
    Pump Whisper-flow 60 gpm DE filter
    Spa: 2013 Hot Springs/salt generator

  6. Back To Top    #6

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    Re: Manganese stains?

    Are you filling your pool with a municipal water source or are you using well water? Well water is more suspect for metals than muni water is.

    I would highly suggest removing the cartridge from your Nature 2 system. Nature 2 adds metals (causes stains) to water. Definitely something that you don't want.

  7. Back To Top    #7
    solarboy's Avatar
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    Re: Manganese stains?

    Isn't your FC a tad low for your CYA? Sure it's not just Algae?
    Self built 5500 gallon bare concrete (temporarily) pool with limestone coping, Pentair Swimmey 1/2 HP pump, Triton sand filter with DE, Simpool peristaltic muriatic acid pump with pH sensor and Monarch SWG. Home made solar heater with Pentair Compool control panel and 3 way valve. 1 skimmer, 1 main drain, 2 returns, 2" plumbing, Hayward auto fill valve.

  8. Back To Top    #8
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    Re: Manganese stains?

    In most cases, less is more. If your adding Jack's Blue and its not solving your problem, why wast your money? What happens if you take a chlorine tab and rub it on the stain? CYA is to high. Do you have your own FAS-DPD test kit?

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    Re: Manganese stains?

    wkussmaul,

    1. Your chlorine results seem odd. Are you using the FAS-DPD powder from Taylor using the 0.2 method or the 0.5 method, if not are you using their liquid, or another product test kit from another company? Are you using, pucks, liquid chlorine, or a saltwater system?

    2. The CYA at 105 is too high it should be no higher than 80 (60 to 80 is recommended), see the CYA/Chlorine chart here:

    http://www.troublefreepool.com/chlor...art-t2346.html

    For the recommended CYA/Chlorine level for a salt water pool, you would need to drain the pool down by 25 ppm or 24% to get to 80 ppm, or 45 ppm or 43% to get to 60 ppm (See edit below for non-saltwater pool levels).

    3. As the CYA is too high it is probable that you might be using pucks, it would be better to use liquid chlorine as this adds no CYA to the pool, or install a salt system if you can.

    4. The chlorine level is too low for a CYA of 105 (Target FC for 100 (not 105) is 11.4, minimum is 7.3), the suggestion that you might have algae seems then valid, as Vitamin C tablets will not remove the stain it is possible that you have Black Algae, nascent Black Algae (less difficult to remove), or at a minimum the start of an algae problem. You will need to raise your chlorine to shock levels for Black Algae, or nascent Black Algae, and shock for 4 -7 days maintaining the high level chlorine (higher than 46.1 ppm for a CYA of 80 ppm, if CYA is 60 ppm then 35 ppm of FC) for the entire time, checking every 8 hours to maintain the level for 4 to 7 days, and yes you can have black algae and no green algae, my neighbour had this issue under similar test results to yours.

    5. You will need to monitor the chlorine level every 8 hours and make sure you pH is ideally in the 7.2 area, as the chlorine works better the lower the pH and the colder the water. It is nearly impossible to know the pH unless you calculate it correctly using the "poolequations" Excel spreadsheet by ChemGeek here:

    http://richardfalk.home.comcast.net/...lEquations.zip

    Do not forget to enable/permit to allow for "Macros" when using the sheet. The easier method to check for pH would be to obtain an electronic pH meter this will then give you an accurate reading very easily. Once you start adding this much chlorine for the shock treatment the pH rises and can offset the cleansing effects of the chlorine, so it is important to know your pH.

    6. Doing the Black Algae shock treatment is a real pain as you need to scrub every 8 hours at a minimum. You can test for Black Algae prior to doing the shock treatment as follows, find an area where these marks are appearing and scrub hard with a steel brush and put a puck on it for 8 hours removing it every two hours and scrub. If the mark goes away you have black algae. In another area put another puck but do not scrub, if that algae remains you have confirmed Black Algae, if it to goes away then you have regular algae, or nascent Black Algae, so not so bad and a lot easier to be rid of.

    If after 4 to 7 days the Black Algae shock has not removed all the stains you can treat as mentioned with a puck. If there are too many spots as was the case with my neighbour we had to drain the pool. We had the pool drained by sunset, we took cotton auto shop towels soaked them in pure chlorine, scrubbed the spots and stuck the towels over them, then scubbed and reapplied the towels every two hours, during the night, this removed the many spots (over 30 of them). You should do this in darkness as the sun can dilute the effect of the chlorine. You have to scrub the Black Algae as it has a strong film on them that is not easily broken even by chlorine, it also grows into the plaster so it is important that you get rid of them completely or the will grow back.

    7. As mentioned I also would get rid of the Nature 2 as it adds copper and I think silver both of which can stain as it did in my pool, "The Blue Stuff" actually removes the copper and possibly the silver so in effect you are "chasing your own tale". If you live in a windy area or your municipal water supply contains iron and/or copper I would continue to use "The Blue Stuff", as I have a salt pool I use the "Purple Stuff" and it works great no more re-occuring iron stains from the wind born dust with iron in it.

    8. To know how much chlorine you have in the pool at these high levels, say 25 ppm, you will need to add 10 times the amount of water to dilute the test and if it reads 2.5 ppm you are at 25 ppm. To do this take 100 ml of pool water and to that add 900 ml of tap water (measure your tap water to see if it to contains any chlorine and offset by that amount when testing), then pour mixture into testing tube to the desired level and test.

    Hope this helps and of course it may not be Black Algae, but if it is you better get rid of it quick as it is virulent and nasty stuff, really hard to get rid of (especially if it grows on the walls), and will damage your plaster. Even if it is not Black Algae, which is entirely possible and I hope is the case, it seems that it is algae, or possibly nascent Black Algae, it would therefore be best to shock it out until it is gone, say 4 days to be safe. Once done use "The Blue Stuff" as this will mitigate/offset the potential for metal stains although it will be quickly used up by the high chlorine. You should scrub the entire pool with a stainless steel brush at a minimum of twice a day to avoid the metal stains appearing on the surface this will also help break up the algae. Hand vacumming to waste once a day also helps sometimes if a lot of algae falls off.

    Finally sorry about the somewhat poor itemized/chronological orderI will try to re-edit it later so it flows better but if you read it carefully I think you will get the general gist of it.

    Later edit for a non-saltwater pool: For CYA target of 40, drain pool down by 62% then fill with fresh water, target FC at 4.6 ppm, shock at highest level of 23.8 FC or above.

    WARNING: IF YOU DRAIN THIS MUCH MAKE SURE THAT YOUR POOL WILL NOT POP OUT OF THE GROUND. CHECK WITH YOUR POOL BUILDER THAT SUFFICIENT RELIEF HOLES WERE DRILLED AROUND POOL TO ALLOW THIS 62% DRAINAGE.

    If not drain 25%, then refill, then drain, 25% again then refill, etc. until pool has a CYA of 40 ppm.
    10,000 gal plaster pool,3/4 hp WhisperFlo pump, Sta-Rite Great White GW9500 pool cleaner, Hayward 300 lb Sand Filter
    Use Magenta Stuff for Iron and Silica control.
    Balance: pH 7.7 Cl 7 -8 Alk 70-80 CH 325 CyA 30 in winter - 50 in summer NaCl 1010 TDS 1200

  10. Back To Top    #10
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    Re: Manganese stains?

    CYA should really be 30 - 50 ppm ( unless you are using SWCG then CYA should be 50 - 80 ppm)

  11. Back To Top    #11

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    Re: Manganese stains?

    Salp,

    Good point, apologies, if your pool is a non-SWG pool then CYA should be 30-50 ppm, I actually keep my SWG pool at 35 ppm but it is only 4 1/2 feet deep so does not really benefit from the 60-80 ppm effect.

    Thank you for the correction.
    10,000 gal plaster pool,3/4 hp WhisperFlo pump, Sta-Rite Great White GW9500 pool cleaner, Hayward 300 lb Sand Filter
    Use Magenta Stuff for Iron and Silica control.
    Balance: pH 7.7 Cl 7 -8 Alk 70-80 CH 325 CyA 30 in winter - 50 in summer NaCl 1010 TDS 1200

  12. Back To Top    #12
    Richard320's Avatar
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    Re: Manganese stains?

    I'd worry more about calcium scaling - scale looks gray, not pearly white like a movie star's teeth. What is your CH reading? The scale (mine anyway) seems prone to absorbing whatever's in the water more than the plaster. I recently discovered a length of rusty chain in one of the strainers. Prior to that, I found that the previous owner tethered his floater with copper wire!

    Scale won't lift with chlorine nor a vitamin C tablet, but it with come off with vigorous brushing. Although, if you pick a particularly dark patch to work over, be prepared for it to be untouched, but the area around it will clean up nice, making that dark spot stand out even more. Ask me how I know!
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
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    Re: Manganese stains?

    wkussmaul,

    Apologies I have not had the time to re-write the above.

    Richard320 makes a good point about calcium scaling, however with the limited information you supplied it seems your CSI is -0.57, it therefore seems unlikely that you would have scaling. Ideally it would be good to get the CSI back to a maximum negative of under -0.30 and more ideally around zero, low level of chlorine makes algae the more likely culprit.

    A good place to input your figures is the "Pool Calculator" here:

    http://www.poolcalculator.com/

    Near the bottom of the page is a "Suggested Goal Levels", change these to match your pool setup. Getting your pool into proper balance will help a lot, also your chlorine usage should drop once this is done.

    Also go to the "Pool School" on this site here:

    http://www.troublefreepool.com/pool-school/

    Lastly if you do shock it would not surprise me if in the first 6 hours you had to add half as much chlorine again just to get the shock levels up to where you started. You will know when the chlorine has done its job when the Free Chlorine (FC) drops by less than 0.5 overnight if you take the reading after sunset and just before dawn, and if Combined Chlorine (CC) is below 0.5.

    It is best to use regular liquid chlorine such as Walmart's Ulta Bleach (Regular not Scented), rather than non-chlorine shock, plus it is easy to return, buy two to three times the shock level.

    Note: Potassium monopersulfate (a common non-chlorine shock) will often show up on tests as CC. There is a special reagent you can get to neutralize the potassium monopersulfate so you can get a true CC reading.

    Hope this helps.
    10,000 gal plaster pool,3/4 hp WhisperFlo pump, Sta-Rite Great White GW9500 pool cleaner, Hayward 300 lb Sand Filter
    Use Magenta Stuff for Iron and Silica control.
    Balance: pH 7.7 Cl 7 -8 Alk 70-80 CH 325 CyA 30 in winter - 50 in summer NaCl 1010 TDS 1200

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    Re: Manganese stains?

    One of the best test kits to test for CC is from Taylor Technolgies, the FAS-DPD-free and combined kit,

    KIT NUMBER: K-1515-A here:

    http://www.taylortechnologies.com/pr...D=1&KitID=2185

    Instructions here:

    http://www.taylortechnologies.com/pr...er&Number=5217

    The liquid drop color kits are too difficult as the color variation is so small. The above kit is much more accurate, as it relies on a simple change from color to clear.

    It is also best to buy it directly from Taylor as the chemicals are fresh. Once you have done the test wash the tube out with fresh tap water and clean the inside out with a paper towel as it leaves a white residue behind even when washed out.

    Finally I doubt it is Managanese stains, even in Hawaii it where we have a fair amount of manganese it is rare to get this type of staining.

    Taylor makes some of the best test kits available, so if you do not have a complete test kit I would recommend you get one from Taylor they are very well regarded.

    Be aware if you do continue with pucks your CYA will always keep rising so you will have to drain back to a CYA of between 30 or 40 every so often, liquid bleach is better but you do have to keep on top of it, a salt water cell ideally with an automatic acid feeder is a great solution for a busy person. Using the last two methods means you should not have to shock unless you let the chlorine get too low. Under normal circumstances you need never shock.

    Hope this helps.
    10,000 gal plaster pool,3/4 hp WhisperFlo pump, Sta-Rite Great White GW9500 pool cleaner, Hayward 300 lb Sand Filter
    Use Magenta Stuff for Iron and Silica control.
    Balance: pH 7.7 Cl 7 -8 Alk 70-80 CH 325 CyA 30 in winter - 50 in summer NaCl 1010 TDS 1200

  15. Back To Top    #15

    Re: Manganese stains?

    Wow, to a beginner like me that's a lot of help on all the previous posts.
    Let me absorb the advice for a bit, try a few things and I will be back.
    BTW, turns out, just after my original post I did experience orange algae on the pool wall for the first time since opening.
    Very difficult to get FC or TC to measure (using sticks), finally got FC up to ~3 ppm, no more algae so far.

    Having come across all the incredible info on this board for the first time this week, I myself am in shock over what I have done to my pool using store chemicals. Ouch!!

    Am going to get a dropper based or digital test system, do better and more frequent testing; switch to bleach for sanitizing. Will have lots more questions as I make this transition, but right now I am surprised to hear than Nature2 causes stains. Has anyone any evidence for this? Not doubting, just asking why a widely used device would cause stains and be recommended by a pool installation company if it was going to be harmful to plaster.

    I fill with municipal water.
    Location: Media, PA (Philadelphia suburb).
    In-ground, 13,000 gallon pool, plaster, built 2008-9.
    Pump Whisper-flow 60 gpm DE filter
    Spa: 2013 Hot Springs/salt generator

  16. Back To Top    #16
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    Re: Manganese stains?

    The pool store folks are mainly trained by the product representatives. There is no "school" or required education to be a clerk in a pool store. As for the builder, unless they get a lot of complaints up front, they are going to use products by manufacturers they have a good working relationship with. When a pool has developed stains 2 or 3 years down the line most people are not going to go back to the builder with the problem. Also, technically this stuff works if you maintain the system exactly according to instructions. That is more hassle than most people want to deal with.

    A digital test system will not be as accurate as a drop based system. I would research them thoroughly before purchasing one.

    There is a google search bar at the bottom of the page. Search pool frog or nature 2 if you would like to read some threads about our members' experiences with those systems.
    TFP Moderator
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    Re: Manganese stains?

    Test sticks are sometimes not that accurate, but are in the main ok for salt and borates.

    This K-2006 test kit from Taylor seems reasonably priced contains nearly all you need and has the added advantange of including the FAS-DPD chlorine test I referred to before, here:

    http://www.taylortechnologies.com/pr...D=1&KitID=2230

    Also I would buy a CyA tube kit (the one with the plunger that goes up and down) from your local pool store and the chemical that goes with it. This makes it easier to read the true level of CyA in your pool.

    This site also sells a test which is well regarded but I have not used it as Taylor chemicals are readily available where I live.

    Once you know your true readings it will be much easier to treat your pool, as persons viewing your issues will have confidence in your readings.

    The only digital item I would buy is a pH meter which you will only use if your chlorine is high at shock levels; otherwise as Zea3 mentioned, digital measuring devices are not normally as good as test kits for the same price.

    And as regards Nature 2, it seems a lot of pool builders give it to pool owners as a "Gift" when they build your pool, then of course one continues to purchase the cartridges, many persons have reported staining in their pools by copper, which was true for me as I used my "Gift" for about 5 or 6 years, most persons do not or cannot, normally because of time constraints, adhere to Nature 2's strict parameter instructions, which if followed may indeed avoid staining issues. This as mentioned above, is most probably why there are many reports of staining. It does kill algae so it most probably did help control the algae in your pool despite very low levels of chlorine, and in a sense did save you from a worse fate. However if you maintain your pool correctly with chlorine you should not require some additional aids such as Nature 2. The "Blue Stuff" if you have metals from any source I am in favor of.

    That yellow stuff sounds like a form of mustard algae read this post here, it is also nasty stuff:

    http://www.troublefreepool.com/high-...ae-t16376.html

    It seems that you are quite lucky so far to get off as lightly as you have, but if it were me I would get on these issues before they become quickly more serious.

    As regards "Pool Store Folks" and even "Builders", I do not think they are bad persons, as often described, but as Zea3 mentioned their recommendations are often what they have learnt from their suppliers. Sadly I have yet, in 16 years, of maintaining a pool gotten any truely compete and all encompassing advice from these persons, snippets yes but mixed with some truely poor advice. From this website and another I have gotten, in the main, the best advice. So while sometimes there is some disagreement here on what to do, or the method of doing it, I think you will find that it is most probably the best place for help in the complete sense. Many chemicals are a waste of time and money and create more problems than they solve, here on this website I think you will learn to avoid these pitfalls.

    Hope this helps.
    10,000 gal plaster pool,3/4 hp WhisperFlo pump, Sta-Rite Great White GW9500 pool cleaner, Hayward 300 lb Sand Filter
    Use Magenta Stuff for Iron and Silica control.
    Balance: pH 7.7 Cl 7 -8 Alk 70-80 CH 325 CyA 30 in winter - 50 in summer NaCl 1010 TDS 1200

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