Mustard algae

[NChen9285]

I am also having yellow stains on my white plaster walls! Mostly on the deep end. It doesn’t seem to go away with brushing. I don’t know how to get rid of it and tried superchlorinstjng. I will try to post a thread with pics

 

[NChen9285]

Hi.
Been a few years since I've been on the forum.
Plaster pool, surface new 3 years ago.
Surface seems a bit more susceptible to staining than previous surface for sone reason (acorns, other cause yellow spots that persist). But, opening pool this year had this staining on deep end. I expected it to recede over time, has not. Not organic, won't brush off with metal bristle brush. Pool guys will tell me to acid wash which I am loathe to do. Read about metals in water, Vitamin tablets, etc. I'm sure obe of you folks know exactly what to do. Please help, thanks in advance.

25,000 gallons.
18x39
Deep end 7'
Cya=30
Alkalinity=110
CH=280
Ph=7.6
TFT-100 test kit

View attachment 591994

Were u able to get it out?!?

I’m having a similiar problem just on the deep end of my walls

 

[Texas Splash]

"285" let's start with a full set of water test results please. Can you post some? Your Poolmath test logs are blank.

 

[NChen9285]

this year I have these yellow stains only on the walls of the deep end

I brush vigorously with a nylon brush and it doesn’t come off. (I was told metal brush shouldn’t be used regularly even on plaster).

Is this yellow algae? Or something else?

Pool store testing results….
35,000 gal white plaster pool
Cartridge filter
Temp 90 degrees
Alkalinity 92
pH 7.7
Calcium hardness 251
cya 5
Phosphate 396 (I already put some phosphate remove to take down)
Optimizer 3
FC 0.2
Total chlorine 0.2

I added 5 bags of calcium hypochlorite and the stain still didn’t come off

The stain appeared when I first opened my pool this year (have a solid cover). Pool water has been pretty clear.

Thanks in advance for any advice!!!

 

[Donldson]

Mustard algae brushes away easily. This sounds more like staining. Do you have a chlorine puck on hand? If so, try rubbing it against the stain and see if it lightens. Lightening would point to organic staining, darkening would point to metal stains.

We really can't say too much regarding the water chemistry based on pool store testing. It's proven to be unreliable time after time, and judging by the direction they've got you running in they don't have a very good grasp of the situation. I'd highly recommend an adequate test kit that meets our needs to help diagnose and correct this issue with you. Test Kits Compared

 

[fredder9]

Were u able to get it out?!?

I’m having a similiar problem just on the deep end of my walls

Not yet. Haven't done more than brushing yet though. I saw someone said try a chlorine puck. I had small, similar stain last year and put a puck on it. Next day moved the puck. Had a perfect 3" circle underneath. I got worried setting the puck would damage surface so left it at that. It eventually faded. This year larger area.

 

[PoolStored]

Not yet. Haven't done more than brushing yet though. I saw someone said try a chlorine puck. I had small, similar stain last year and put a puck on it. Next day moved the puck. Had a perfect 3" circle underneath. I got worried setting the puck would damage surface so left it at that. It eventually faded. This year larger area.

For the future, you don't want to leave the puck, just rub it over the area for a few seconds to a few minutes and it should lift if it organic.

To remove organic stains raise the FC up between 60% and 100% of SLAM level for your CYA, and brush often, daily if you can.

 

[fredder9]

For the future, you don't want to leave the puck, just rub it over the area for a few seconds to a few minutes and it should lift if it organic.

To remove organic stains raise the FC up between 60% and 100% of SLAM level for your CYA, and brush often, daily if you can.

Yeah. I'm positive it's not organic. I do use SLAM method when I open and was considering doing that now to see results but have had a lot of swim days - I know it's not harmful just haven't done that yet. Maybe this weekend while family away.

 

[fredder9]

Yeah. I'm positive it's not organic. I do use SLAM method when I open and was considering doing that now to see results but have had a lot of swim days - I know it's not harmful just haven't done that yet. Maybe this weekend while family away.

....or should I not be so positive it's not organic just because I can't brush it away?

 

[PoolStored]

Here is the complete stain id guide...

Stains in Your Pool

The stained pool is beyond embarrassing. Our in-depth Guide to remove stains in your pool will help you to remove the stains and prevent them in the future.

www.troublefreepool.com

 

[fredder9]

Here is the complete stain id guide...

Stains in Your Pool

The stained pool is beyond embarrassing. Our in-depth Guide to remove stains in your pool will help you to remove the stains and prevent them in the future.

www.troublefreepool.com

Thank you I will read through this.