Mustard algae?????


Well-known member
May 8, 2007
El Paso, Texas
Today was the first swim of the season, the pool has been clear, what I noticed while swimming was the floor was kinda slippery, I dawned the goggles and used my brush to brush the walls and floor, what I noticed was a kind of powder/haze when I brushed, as I kept on brushing, the pool was getting cloudy, is this the start of mustard algae???? If I brushed the wall with my hand same thing, kinda slippery, followed by a white cloud. Pool is over 2yrs old.

here are my numbers

FC 10
TC 10
CC 0
PH 7.2
CH 600

I know my cya is high and have been keeping my FC up

What do you all think??????


Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
Sebring, Florida
Hey, Rock,

It doesn't sound like mustard algae to me. Mustard is commonly misdiagnosed so I'd assume it's regular algae and shock the pool up to about 25ppm or so. Hold it at that level for a couple of days and brush the floors and walls also. Keep your pump running. My guess is that will cure what I would suggest is just a lingering case of algae.

Mustard algae typically is brownish rust in color, likes to grow on the shady side of the pool and brushes up like dust but is back in the same spot the next day. It sounds like you have a more generalized condition.


Well-known member
May 8, 2007
El Paso, Texas
I added about 1 1/2 gallons of bleach, using the taylor 100 test kit, I think I am at 25, is there another way to test clorine higher?? is there any harm with high amounts of clorine (bleach)???