Is this algae? Pool shop recommending algaecide and clarifier

Dandelion

Member
Aug 23, 2020
19
Brisbane
My pool seems to constantly have green dust on the bottom. The water is clear but If I brush the bottom and sides it kicks up. PH and TA is fine, CYA at 50. Chlorine has been held at 5-6 PPM. If I run the cleaner (Dolphin s200)I’m not sure if it actually picks it up or just kicks it off the bottom to resettle.


started a slam at 27ppm and the cl isn’t dropping like I’d expect if it were algae. In fact it’s going up because I went camping on the weekend and threw a tablet in while I was away even though I normally use liquid chlorine.


I called 2 local pool shops and they both said chlorine bleaches algae and I should use Algecide and clarifier and vacuum to waste. I know this goes against TFP methodology but I’m getting a lot of pressure at home to listen to “local experts” rather than “some guys on the internet”

Has anyone come across this before and fixed it?

This is what it looks like:

 
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know this goes against TFP methodology but I’m getting a lot of pressure at home to listen to “sales people trying to make money off of me” rather than “some guys on the internet”
Fixed your quote for you :)
 
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Sounds like possibly mustard algae. Do you have pictures?
I don’t, I’m not at home this week and my partner’s phone camera doesn’t work unfortunately.

I didn’t think it was mustard algae because it doesn’t clump at all, in fact you can’t even see it without brushing it to kick it up. If it is brushed or cleaned you can see the spot difference between brushed and unbrushed but it’s subtle.
 
Actually i did have a similar issue with dusty walls and floor. Turns out polaris sells a filter with a finer mesh. I got it and it picked up all that dust the the original filter was missing.
 
My pool seems to constantly have green dust on the bottom. The water is clear but If I brush the bottom and sides it kicks up. PH and TA is fine, CYA at 50. Chlorine has been held at 5-6 PPM. If I run the cleaner (Dolphin s200)I’m not sure if it actually picks it up or just kicks it off the bottom to resettle.


started a slam at 27ppm and the cl isn’t dropping like I’d expect if it were algae. In fact it’s going up because I went camping on the weekend and threw a tablet in while I was away even though I normally use liquid chlorine.


I called 2 local pool shops and they both said chlorine bleaches algae and I should use Algecide and clarifier and vacuum to waste. I know this goes against TFP methodology but I’m getting a lot of pressure at home to listen to “local experts” rather than “some guys on the internet”

Has anyone come across this before and fixed it?
Pool RX is the only stuff I have used for 10 years without issues. Add a booster with the capsule twice a year. Best stuff I have honwstly ever used. Some will call it snake oil, but it has made my pokl car soooo easy, that I swear buy it.

Good luck!
 

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Pool RX is the only stuff I have used for 10 years without issues. Add a booster with the capsule twice a year. Best stuff I have honwstly ever used. Some will call it snake oil, but it has made my pokl car soooo easy, that I swear buy it.

Good luck!
I thought you were building currently? Maybe you are talking about a prior pool?

I was curious on the product and saw that it is basically a mineral cartridge. Are you telling is that for 10 years that is all you used, or is it that you used chlorine + this stuff?
 
Have you done an Overnight Chlorine Loss Test? Try that, it will surely help you determine if there is something organic in your pool's water.
I did one last night. It might have lost 1-2 ppm between about 7pm and 7am. When I do multiple tests of the same sample it can vary so I'm not really sure how to take that result.

I finally have a video of what the stuff looks like:

 
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I thought you were building currently? Maybe you are talking about a prior pool?

I was curious on the product and saw that it is basically a mineral cartridge. Are you telling is that for 10 years that is all you used, or is it that you used chlorine + this stuff?
Ya used it in my prior 15k gallon pool and loved the stuff! Sold my uncle on it as well who lives in San Diego and was getting lots of green water from full sun and cover on to warm the pool. Pool #'s were all good so I told him to pop a Pool RX in and next day he calls me and tells me the stuff is incredible I've never had it go from green to clear so quick and it's been good ever since.
So for 10 years I used Pool RX I would replace the cartridge once a year, and then twice a year I would add the booster. I had a SWG for my chlorine production. Then floater tabs in the winter here in California.
 
Dandelion,

1. Do some more research. Mustard algae doesn't "clump". What it DOES do is look exactly like the "dust" you are pushing around your pool.

2. Decide who will manage the pool water chemistry. You seem to be managing by consensus rather garnering factual information and let one person (even if it's not you) make the decisions.

3. Stay out of the pool store. The information you are getting there is false and confusing.
 
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mihzyd777,

With over 100 posts on this forum. I am surprised you would post something with so much misinformation.

Please read "The "ABC's of Pool Water Chemistry" up in Pool School. You will find that your method of pool care is wa-a-ay off from what we teach and that pool rx is a copper and zinc containing product that we would never suggest here at TFP.
 
Dandelion,

1. Do some more research. Mustard algae doesn't "clump". What it DOES do is look exactly like the "dust" you are pushing around your pool.

I got clumps from here: Mustard Algae - Trouble Free Pool


The other thing is it’s been held at shock level for like 4 days now, and the dust keeps accumulating even after brushing and vacuuming and according to that TFP article mustard algae doesn’t do that.

Not that I know what it is, and I’m open to just treating for mustard algae just in case but I’m not sure about how to start. The wording in the article is a bit ambiguous.

It says shock like normal and then bring it up to mustard algae levels. I’ve done the first part but it won’t pass an overnight test after 4 days of it being held above 22ppm, more often closer to 30. Do I keep shocking it until it passes an overnight test and then treat it for mustard algae or just bomb it with chlorine now anyway?
 
In a nutshell, follow the SLAM article. Finishing the SLAM requires three things...
A. Pool water should be crystal clear with no sign of algae (or "dust" anywhere
B. CC's test result should be .5 ppm or less
C. You should not lose more than 1 ppm FC overnight.

Next, follow the protocol for mustard algae. (I am not really positive that is mustard algae but following that protocol causes no harm and adds very little expense)
 
I did one last night. It might have lost 1-2 ppm between about 7pm and 7am. When I do multiple tests of the same sample it can vary so I'm not really sure how to take that result.

I finally have a video of what the stuff looks
Yup that is dead algae, you have enough suspended algae, that you can't see it,, but as it dies it accumulates on the bottom and you can sweep it like that. Just like @duraleigh suggests keep up the SLAM until you pass .
 
mihzyd777,

With over 100 posts on this forum. I am surprised you would post something with so much misinformation.

Please read "The "ABC's of Pool Water Chemistry" up in Pool School. You will find that your method of pool care is wa-a-ay off from what we teach and that pool rx is a copper and zinc containing product that we would never suggest here at TFP.
Hi thanks for letting me know. Can you olease point me to a topic that discusses this. I never said that was my onky method of keeping my pool clear and clean. I absolutely follow the ABC's and use it simply as a Dd on to make life much simpler. I used it for 10 years Nd almost everyone who came to my house aoukd always mentioned how nice and clear my pool water looked and when I tested my pool water once a week with Pool RX in the onky thing thatvwas off was PH from the natural Ph rise from salt.
 
Can you olease point me to a topic that discusses this.
That's pretty hard to do. We don't publish general information on all the stuff that DOESN'T work (it would be voluminous) but, instead, we try to publish information that DOES work and fits within the TFP method of pool care.

The "clumping" description you found is an error on our part and that will be corrected.
 

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