Mustard Algae? Brown splotches on pool floor

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
Lil Davy
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Mustard Algae? Brown splotches on pool floor

Postby Lil Davy » Wed 02 Jun, 2010 08:12

I'm trying to figure out what my problem is, and now, from reading several posts, I'm wondering if I don't have two problems.

The first problem, which I didn't think was a problem, is that I keep finding these brownish clumps, almost like dust bunnies that I attributed to "gathered dirt", etc. From reading, it sounds like these may be mustard algae, but I'm not sure. I always have the filter running, and the water is crystal clear - and I always have the solar cover on when not in use. Could these clumps be mustard algae? Does anyone have any pics of this?

My second issue that I just discovered yesterday is brown splotches in the pool bottom. They look like stains that are now covering about 10% of the bottom. I tried brushing it and they didn't come off. These splotches weren't there two days ago. I'll have to get the chemical readings when I get back home, but I'm just trying to do some homework to figure out what I am dealing with.



Mustard Algae? Brown splotches on pool floor

Postby Blazing » Sat 28 Aug, 2010 17:16

Yes, You have algae. Check out my web site solvemypoo and read the sections on algae on pool surfaces and on water chemistry. keep in mind that this is based on over 25 years of pool and spa service in one of the most difficult areas to maintain proper water chemistry, Phoenix Arizona. The information is good for both above ground and inground pools, and should keep all of your pool problems at a minimum as, when followed, and the equipment is operated as it should be, I have had only one pool with algae in 5 years. This includes the pools of the people I have trained, and their pools as well. (That's about 250 pools serviced once a week for 5 years.) If the information I share there is followed, your problems, both now, and in the future, should be minimized.
chem geek
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Location: San Rafael, California

Mustard Algae? Brown splotches on pool floor

Postby chem geek » Sat 28 Aug, 2010 22:59

Note that your prescription on your website has a COMPLETE water replacement every 2 years when using filters that backwash and every year for cartridge filters. There are many pools in areas with water restrictions, such as where I live, where this is simply impractical. It is not necessary to replace the water -- you are doing so because you are using stabilized chlorine and the Cyanuric Acid (CYA) level will rise over time making the chlorine less effective.

Yes, the water should eventually be diluted and can be done using summer/winter rains, if available, or through intentional dilution, but it doesn't have to be as much as you indicate in all pools. You describe an area with a high Calcium Hardness (CH) and lots of hot weather and sunlight (i.e. Arizona) so evaporation and refill will add whatever is in the fill water into the pool so dilution is needed to keep the CH lower, but not all pools in all areas have this problem.

See this post I wrote in response to another one you wrote in a different thread for more info.

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