Black dust - could be algae - on bottom of pool

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
floridapooltech
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Black dust - could be algae - on bottom of pool

Postby floridapooltech » Wed 28 Jul, 2010 09:56

That does not sound like a phosphate problem. Also, "Phosfree" is not a good choice of phosphate removers as all natural chemistry products contain even more phosphates, defeating the purpose to begin with. The best phosphate remover on the market is made by SeaKlear http://www.swimnsaveusa.com/phosphateremover.html. Have you tried cleaning out your filter and running the pump for a full day? This may help as you will need to cycle your entire pool water several times to clear out any contaminants.


chem geek
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Black dust - could be algae - on bottom of pool

Postby chem geek » Wed 28 Jul, 2010 10:51

I don't believe that Natural Chemistry products contain phosphates. Do you have a specific product you believe does? I can show you the MSDS for its ingredients. Phosphates aren't a problem anyway if one maintains a sufficient Free Chlorine (FC) level relative to the Cyanuric Acid (CYA) level since chlorine alone can kill algae faster than it can grow regardless of phosphate (and nitrate) level.
b

Black dust - could be algae - on bottom of pool

Postby b » Tue 09 Aug, 2011 12:59

We found out our lifeguard kids were bringing home lake algae and introducing it into our pool when they dived in after work..
Do not let anyone dive into your pool who has been in a lake or natural body of water. wash hair take a soapy shower also.
As a matter of fact we have seperate bathing suits .or you can wash your bathing suit before going in a pool with it.
Good luck/ We still battle brown algae dust anyway. I vaccumm it before we go in
over thinking

Black dust - could be algae - on bottom of pool

Postby over thinking » Wed 10 Aug, 2011 09:10

Black dust will most of the time be from someones roof dust that gets blown into the pool. If you had black algae it would not vacuum up nor any stains.
bajllc

Black dust - could be algae - on bottom of pool

Postby bajllc » Sun 17 Jun, 2012 20:14

over thinking wrote:Black dust will most of the time be from someones roof dust that gets blown into the pool. If you had black algae it would not vacuum up nor any stains.

I have the black dust in the bottom of my pool too. I use the saltwater pump system with a sand filter pump. Not too long after I vacum up the "dirt" it comes right back. What did you do for yours? I am certainly hoping it is not any kind of algae. It seems to form in the seams of the pool but brushes and vacums right up. It looks like dust when it is stirred. No clouds or water problems that I see
alligratorthenyou

Black dust - could be algae - on bottom of pool

Postby alligratorthenyou » Wed 08 Aug, 2012 09:33

i have this black stuff on the bottom of the pool. i dont know if its algae. weve tried everything. it doesnt come off it just sits on the bottom of the pool. we have tried to scrub it off with a hard brush but it scraped the liner. does anyone know what it is
RM

Black dust - could be algae - on bottom of pool

Postby RM » Mon 20 Aug, 2012 17:14

Did anyone find a solution for this? I have the same problem. Small patches that look like dirt and they vacuum or brush away instantly. They come back a few hours later in the exact same spots. I've been running my Salt generator at 100% for 2 days and still can not get rid of them. My chlorine is very high at the moment and I would think Algae would be gone. Any help appreciated.
idieh

Black dust - could be algae - on bottom of pool

Postby idieh » Mon 17 Sep, 2012 15:56

Have the same problem with our inground pool. Am told that it is a black algae that is a pain to get rid of.

According to this website, www.justanswer.com/home-improvement/Ouf ... -thay.html, there is a way to battle it so am going to try it. Remember dealing with it a few years ago, and had a fantastic pool guy that helped me but didn't remember what I had done and my guy is no longer in business. :(

One thing he always told me was everytime I put liquid chlorine in the pool, was to also put in 1 C of Acid. Needless to say I haven't been the one doing the pool chems and no longer have the same pool guy so it shows.

Good luck everyone
JIvories
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Re: Black dust - could be algae - on bottom of pool

Postby JIvories » Wed 09 May, 2018 06:37

Ok, this thread is 6 years old, but I have the same problem. Black dust, maybe a kind of algae, that dissipates quickly when you brush or vacuum. Then reappears because too fine for filter. Have people on this list found any solution other than vaccumming it all to waste (which wastes a lot of water and you have to do it repeatedly)?

I think I tried clarifier last year and it didn't work. Is flock the answer, to pull in together, then vacuum to waste or let filter?

Someone could make a lot of money by coming up with the right product for this!
Teapot
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Re: Black dust - could be algae - on bottom of pool

Postby Teapot » Wed 09 May, 2018 15:26

Black algae is a black coloured bacteria and isn't free floating so what you have is fine silt. How insanely powerful is your pool pump compared to the tiny sand filter I am guessing you have, sizes please.

Slowing down filtration speed can increase your filtration efficiency by around 4x. It can save a truck load of money in electricity to. What I generally do is put a good cotton towel in the skimmer, put the vacuum plate over the lot and vacuum the fine silt up. Pointless if your pump is too powerful as the dirt gets dragged through, gently is better. Full power is ok for backwash but not for filtration.

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