Algae On Sun Facing Wall

[diamonddog]

22K Gallon Salwtwater Pool -

FC 4 ppm
ph 7.5
Borates 50
TA 90

I am getting mustard algae only on the wall of the pool that faces the sun. Its not a ton, but it grows and I have to sweep it off a couple time a week

 

[mknauss]

CYA level.

That is not the normal presentation for mustard algae.
Follow the SLAM Process

 

[diamonddog]

CYA level.

That is not the normal presentation for mustard algae.
Follow the SLAM Process

I knew I forgot something CYA = 70 Water temp is 75

Isnt Slam used when low Free Chlorine levels? I have good Free Chlorine and always have

 

[mknauss]

You have algae. The remedy is the SLAM Process

 

[Rancho Cost-a-Lotta]

Do you use a solar cover?

When you complete the SLAM try running your FC levels a bit higher (Target 7, Min 5). The higher FC won't be noticeable to swimmers, but it will provide a bit of cushion for testing errors and increased FC loss.

Follow the mustard algae protocol after completing the SLAM. Take your time and do it right the first time. Unfortunately, there's no easy way out.

With a CYA of 70, you'll have to run some pretty high FC levels during the SLAM. When testing to maintain SLAM FC level, you can use a 5 mL water sample to conserve reagents. Use one scoop of powder. Each drop of R-0871 counts as 1 ppm. I use an infant medicine syringe for accuracy and consistency.

Good luck. Let us know if you need any help.