Mustard Algae?

[rgrountree]

I have few spots of mustard type algae that are popping up in a few places around the pool. Mostly in the spa and bench areas. These spots brush away quite easily but I am wondering what is causing these to continue popping up. I have not had this issue the last 2 years.

From Test this morning
FC = 2 (Target 5, adding bleach daily)
CC = 0
pH = 7.6
TA = 60
CYA = 40-50

I have never shocked the pool, as I have never had any combined chlorine or previous algae issues with the pool - Thanks TFP!

I am wondering if I need to shock or if I need to just adjust my target chlorine level up given my CYA.

Thanks in advance for your input!

Rawlins

 

[Abigail K]

Increase your target FC.
FC 2 is below the minimum for your CYA.

 

[aasbury]

From experience, Mustard Algae can be a PITA. You can brush it away only to have it reappear a short time later. There is an article on here that discusses how to rid yourself of it. My advice is to raise your chlorine to MA shock level and brush until exhausted and then brush a little more!

 

[rgrountree]

Thanks for the suggestions.

I completed an OCLT test overnight and saw only a 0.5 PPM drop in free chlorine. So this is good news I suppose. I will push up my target FC levels based on CYA.

 

[aasbury]

Thanks for the suggestions.

I completed an OCLT test overnight and saw only a 0.5 PPM drop in free chlorine. So this is good news I suppose. I will push up my target FC levels based on CYA.

Don't forget to keep brushing...