How easily is mustard algae brushed away?

[Herdo]

I've read that unlike "regular" algae, mustard algae is "easily brushed away", but how easily? Is it still attached to the surface?

I've got a fine layer of dust covering my entire pool every morning and I've been keeping the chlorine levels high (around 12 ppm), with no combined chlorine. This stuff doesn't even need to be touched to be removed. Even just moving your hand over the area is enough to blow it out of the way. Here's a short video.

As you can see, it's just sitting on the surface. Anywhere the barracuda vacuum goes leaves a perfectly clean area as well. Is this indicative of mustard algae or is it likely to be something else? It's got a yellow appearance to it, but the high chlorine and no CC leads me to believe it's probably not algae.

I've noticed that my return valves pump out a brownish slurry everytime it's been off for a while, making the water cloudy. I'm assuming this is something my sand filter is not capable of filtering.

My next step today was to try adding a bit of DE to the filter using the guide found on this site.

Any other advice?

 

[mknauss]

What are your test results? Looks like you need to follow the SLAM Process

 

[Herdo]

What are your test results? Looks like you need to follow the SLAM Process

FC:10 (it was 11 - 12 yesterday)
CC:0
PH:7.6
TA:90
CYA:50 - 60

Regarding the CYA, I use the BBB method and generally keep this low (around 25-30), but the pump broke this winter and my landlord just kept dumping tons of shock in to keep it clean until he could fix it (3 months later...) , which raised it substantially. I plan on draining some water eventually, but 50 - 60 didn't seem too high so I'm leaving it for now.

So it sounds like you believe this to be algae? I guess it's back to the pool store to drop another $60 in liquid chlorine and some acid. Yay!

Thanks for the reply!

 

[mknauss]

Look for a HASA dealer for chlorine.

SLAM level FC for a CYA of 60 is 24 ppm.

 

[Herdo]

Look for a HASA dealer for chlorine.

SLAM level FC for a CYA of 60 is 24 ppm.

Well I put in 8 gallons of chlorine, which should have gotten the FC to near 40 ppm.

Woke up today to a blue pool, and no sediment, so I'm assuming this was in fact algae. Now it's just a matter of running the pump enough to get the water clear.

Thanks again for the help!