White Mold

So I'm being told I have something called white mold in my pool. It looks like very fine white/light gray sand gathering in different spots on the bottom of the pool. It's so fine that it essentially dissipates when you touch it. It ranges from the shallow end to the deep end. We had it earlier in the season and didn't recongize it so we didn't do anything. For a period of time it went away. One, does anyone have a way I can determine if it really is white mold? The "diagnosis" came from the pool store so that's essentially worth nothing. Secondly, if it is in fact white mold, what do we need to do to get rid of it? Thank you very much.
 
The best way to find out of it's anything organic is to run an OCLT. Do you have a good test kit?

White mold is usually a gel like substance that's slimy to the touch.

Is it slimy whan you touch it? It could just be dead algae.

Post a set of test results and how you got them?
 
Over night chlorine loss test. Check your FC level when the sun is down adjust if needed and recheck. Remember the level. Check FC next morning before sun comes up and see if you lost any FC. If you lose more than 1ppm something is consuming your chlorine.


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Aspfam said:
I have a the TF-100 test kit. Does that test for it?

The test kit does not test for the presence of mold. What it tests for is the presence of combined chlorine which is an indicator of something organic in the water. Posting the typical test results let's everyone see if your water chemistry is out of whack. From there we can make good recommendations rather than guessing.

Dust on the bottom is probably dead algae assuming your water chemistry is ok. White mold will be a slimy gel if it's clumped up. It might look like floating tissue paper in smaller quantities. I found it in two places in my pool. It was growing wrapped around the line that anchors the floating thermometer and in the filter basket. The skimmer basket was clear but the filter basket which is next in line had mold growing throughout the openings. Mold likes low chlorine levels and dark places.

The float line just felt a little slimy since it is in the sun. The filter basket was choked with mold. It looked like white bread dough growing through the holes in the basket.

You need to post FC, CC, PH and CYA at a minimum. Read pool school it will help.

I know pool school and everyone here helped whip my pool into shape. In my case, the CYA level was off the chart so my chlorine levels were too low.
 
The OCLT will tell you if something is "eating" your chlorine. It takes some time but it is the definitive test. The presence of CC at higher levels is an indication of something organic, but it's possible to have little or no CC and still have something growing in the pool.

In my case, my water was clear, CC was low but I was fighting algae outbreaks every couple of weeks if I let the FC drop too low. Finding a filter basket full of mold was the breaking point for me. I got online, found TFP and took control of my pool. It's a work in progress but I feel better knowing what is going on.
 
Mustard Algae

We're still working on getting our pool numbers in line. As of last night our CYA was only at 30 and our chlorine was at 1-2. My wife has been noticing a "slime" on the sides and a white powder developing at the bottom. Similar to the way sand would accumulate in patches on the bottom. We do fill the pool with well water which I have been told is more likely to get mustard algae. Any suggestions for determining what it is and how to kill it?
 

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Re: Mustard Algae

Is this the same problem you were asking if it is white mold? If so do not start a new topic, keep all of the discussion in one place so we can see what has already been covered and what you have done.
 
Re: Mustard Algae

Aspfam said:
We're still working on getting our pool numbers in line. As of last night our CYA was only at 30 and our chlorine was at 1-2. My wife has been noticing a "slime" on the sides and a white powder developing at the bottom. Similar to the way sand would accumulate in patches on the bottom. We do fill the pool with well water which I have been told is more likely to get mustard algae. Any suggestions for determining what it is and how to kill it?

At 30 CYA your chlorine is too low. Read the relationship in Pool School between CYA and chlorine. At 30 CYA your minimum FC level is 2, your target FC level is 4 and your shock level is 12. Without a good test kit and some solid numbers its hard to tell you what to do. Reread the previous responses. It's all good advice.

It's a lot to read. I know it was for me. I read pool school and watched what the experts recommended until I understood why they gave the answers they did. It took some time but it finally started to make sense.

I'll give you an example from my pool. I have a 16,500 gallon pool. The pool calculator tells me that 128 oz (1 gallon) of 12.5% bleach (sold as pool shock) will raise my chlorine level about 7.5 points. The label on the box said it will raise the level in my pool 8 points so the numbers match.

If my FC was 2 (like your pool) and I wanted it to be at least 4 I would put in about half a gallon. That much will raise my FC in my pool 3.5 - 4 points for a total of about 6 points. Higher than 4 with some cushion. I don't have to really measure the bleach because half a bottle is pretty easy to eyeball. Make similar additions to get to a shock value of 12.

This assumes I have good numbers for the starting point and I know what my chemicals do to my pool. To figure that out you need to use the pool calculator and start with good numbers.

I'm fairly new at this so I can relate if it's a lot to learn.
 
Makes sense to me. It now seems to be mustard algae instead of white mold. Our neighbors apparently get the same thing. Any recommendations for fighting this? I've also come to the conclusion that my SWG is not nor never has really worked correctly despite the claims of my installer(installed in May 2013). We have run it at 100% for 72 straight hours and still register 0 chlorine. I posted a no flow issue questions a few days ago but the installer has always focused on the filter when they should have taken the SWG apart to make sure it was installed correctly and that all the parts are functioning properly. That issue is what caused my water to fall apart and some of these issues to arise. Any tips on the mustard algae would be appreciated.
 
Aspfam said:
Makes sense to me. It now seems to be mustard algae instead of white mold. Our neighbors apparently get the same thing. Any recommendations for fighting this? I've also come to the conclusion that my SWG is not nor never has really worked correctly despite the claims of my installer(installed in May 2013). We have run it at 100% for 72 straight hours and still register 0 chlorine. I posted a no flow issue questions a few days ago but the installer has always focused on the filter when they should have taken the SWG apart to make sure it was installed correctly and that all the parts are functioning properly. That issue is what caused my water to fall apart and some of these issues to arise. Any tips on the mustard algae would be appreciated.
If you have algae, the your SWG wont keep up. Once you get your algae killed you should increase your CYA to the range recommended for SWG, otherwise it will have trouble keeping up.
 
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