Not really sure what this is...

[howbout]

I have a inground pool that I maintain myself. All my numbers are perfect - I can't recall them off the top of my head to post them but they are

However, in the past two weeks (despite everything being balanced) I have noticed a yellowish looking sediment in the pool. I don't THINK it is algae b/c I don't have to scrub it off the walls - it is like dust if I brush it, just billows up into the water with no effort at all. My barracuda vaccums it up with no problem, but of course there are areas it is missing.

Anyway, does anyone have an idea of what this might be? Could it simply be fine debris from lawn mowing, etc.? Or am I dealing with dead algae? If so, how could I even GET dead algae if I haven't shocked or done anything to kill algae in the first place? (In other words, I don't get how it could be algae b/c I never had anything LIVE in the first place).

HELP! What is this? What can I do to get rid of it and prevent it from happening again?

Edited to add that I read the other threads on yellow algae...this does not feel slimy in any way, I reached in and touched several areas where it looks yellowish and it only feels like the pool surface, no slime. The stuff is like silt.

[Poconos]

You don't say what kind of filter you have. Type, size, and pump size are important pieces of info. If it's a sand filter the stuff is probably too fine to be trapped. Could be silt, pollen, dust, dead algae, or all of the above and other things. If you read more threads you'll find some of us with sand filters add a little DE powder through the skimmer and it basically plugs it a little to trap smaller particles. Since I hardly even backwash I do have that fine stuff too and during swimming season I do the DE trick but now I just let the stuff settle and I'll deal with it in the Spring. Post the additional info and we'll go from there.
Al
Edit: I had an interesting microscope pic posted but deleted it because I'm out of space but I'll resurrect it in alittle bit.

[howbout]

Thanks for the reply...still not sure what it WAS but it's gone now. I ran my barracuda all day yesterday then shocked and ran the pump (not with the barracuda) all night long and this morning it was clean again. I am GUESSING it was just fine dirt/silt or something, b/c I don't think an algae problem would have cleared up THAT fast (I have dealt with algae before). It was super cloudy yesterday and honestly is sparkling today, so go figure

But I'll take it!

Thanks again!

Oh - I have a regular filter pump, not sand.

[matt4x4]

I'll bet you that within days, it will reappear. What you have is mustard algae, it starts as a fine yellow/brown layer almost like clay dust and will show especially in any crevices.
Currently, you've suspended it by running the barracuda, it will settle and grow quickly on you.
The ONLY way you can get rid of it without fighting it for months and months is if you shock really high for 3-4 days, by really high, I mean getting your free chlorine up to 20 - 25 ppm and keeping it there, while running your vac to suspend the algae and allow the chlorine to completely surround it and kill it off.

Others will chime in here and disagree with me, some others will want numbers before they will give advice, but the only thing that's going to work for you right now (whether ph and alk is high, low or indifferent) is shocking the heck out of it.

You can follow my advice or not, up to you, but this past summer, a number of people had this algae and the only way they managed to get rid of it is the way I posted above.

[howbout]

I'll bet you that within days, it will reappear.

The ONLY way you can get rid of it without fighting it for months and months is if you shock really high for 3-4 days, by really high, I mean getting your free chlorine up to 20 - 25 ppm and keeping it there, while running your vac to suspend the algae and allow the chlorine to completely surround it and kill it off.

Thank you for your post, but as I stated, I shocked the pool and ran my barracuda. This was well over a week ago. The pool cleared up and has been crystal clear since. I have not had to shock it again, just maintain the balance. The pool looks beautiful.

[matt4x4]

You probably got your chlorine levels high enough and caught it at the beginning stages, excellent to hear it's cleared up, at least you'll know what to do immediately the next time you see it - this particular one can get nasty.