To mustard slam or not


New member
Oct 17, 2018
I haven’t yet made a signature but our pool basics:

27000 gal vinyl
3/4 HP Hayward Pump
Sand Filter
Hayward Aquarite SWG with T-15 cell

We use a solid safety cover and opened to a relatively clean pool. Vacuumed 48 hours after initial opening to clear debris. Noticed a lovely chlorine odor when I put the hose in followed by a few yellow patches that poofed in the sunny shallow end dead zones. Began SLAM process with following chemistry based on my test kit;

PH 7.2
TA 60
CYA 50
CH 200
Salt 2700 (SWG currently off)

On night 4 passed OCLT with FC 22 and CC 0 (that gallon from HD seemed a little stronger). Pool has always been crystal clear. Ladder is out and has been scrubbed with bleach for install. Only thing in pool is an inflatable shark because #ducks (he seems to work well).

The question is to mustard SLAM or not. The original spots were about 2-3 areas the size of pennies. Dark yellow to brown. Never had cloudy water.
Last edited:


TFP Expert
LifeTime Supporter
Jan 6, 2010
San Dimas, CA (LA County)
Mustard algae tends to grow in the shady areas.
So on one side, it probably wasn't mustard algae.
But you're already so high on FC, that bumping it up to mustard levels won't take much bleach.

It really boils down to your peace of mind.