this looks exactly like the mustard algae in our pool. When it dies it lightens. We’ve been fighting it all summer with super shocking and vacuuming to waste. Currently adjusting Ph high and Chlorine low to use Yellow Gone. After coming across this site we are also ordering different steps to replace our wedding cake steps. I read further and saw where you said it was fine sand. Is your issue resolved?
Mustard Algae ?
- Thread starter MichelleF71
- Start date
- Jun 24, 2021
- 16,209
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
Hey! Welcome to TFP!!! 
Do you have a test kit? If not this is the best place to start with a kit. Link-->Test Kits Compared
This is the way we get rid of ALGAE...with a SLAM. Print this out, read it three times. Get a test kit if you don't have one, and start this process. It will rid your pool of algae. Please don't use Yellow Gone, it will cause more problems (ask me how I know).
www.troublefreepool.com
Do you have a test kit? If not this is the best place to start with a kit. Link-->Test Kits Compared
This is the way we get rid of ALGAE...with a SLAM. Print this out, read it three times. Get a test kit if you don't have one, and start this process. It will rid your pool of algae. Please don't use Yellow Gone, it will cause more problems (ask me how I know).
SLAM - Shock Level and Maintain
We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.
www.troublefreepool.com