Pool Closing Headache

Been using the BBB for 2 years, no problems until 2 weeks ago. had a bad storm blow thru. rain,wind, the usual. cleaned up leaves twigs & a ton of general junk that ends up in the pool. was running the usual numbers as follows.
Chlorine 6/8ppmFC ~ 0CC
PH @ 7.4
Alk @ 130
Cya @ 50/60
Started to cloud upafter the storm, still didn't have any CC when tested so i figured i would shock it. ran it up to 16ppm overnite with a loss of < 1ppm. after that i started getting a somewhat dark green almost brown deposits in the cracks of the liner on the bottom, vacumed up everything & overnite i had the same thing. held 6/8ppm fc & 0CC. i can't get rid of the stuff, i have tried to capture it with my fingers, but as soon as ya touch it it's gone, do not have to scrub it with the vacume, but you need to let it sit there for a second to pick it up. ran fresh numbers this morning after shocking it yesterday,
Chlorine ~ 16ppmFC & 0CC
Ph ~ 7.4
Alk ~ 130
Cya @ 50
I will check tonight after the sun get off of it & hold it @ 15/16ppm overnite & see what i have. Anyone have this same problem ? it's driving me nuts & i need to close. Any help would be GREATLY Appreciated, Thanks, Mike
Also the water is crystal clear, it's just the deposits on the bottom, Thanks again

i have no need to "close" my pool for the winter where im at, but your post is interesting to me. i also cleaned up a mess after isaac came through, and had a bit of a chlorine demand, but it has been taken care of. like you i have been noticing some brown "dust" on the floor that is back in the pool within just a couple of days after vacuming. my "dust" will settle around a few wrinkles and in a few small dips. it has been windy here so i have just chalked it up to dust from the wind collecting on the floor. im also crystal clear with a CC of 0 and have recently shocked. my "dust" seems to vacume up just fine with little effort. if you disturb it it will just kinda wisp away...

ill be keeping an eye on this post.

It is probably just dirt/dust. It's pretty common to have that settle around the lines/cracks/seams. I often have the same thing happen in my pool. Vacuum very, very slowly and try not to stir it up so it won't go into suspension in the water. That is really all you can do. I can usually do a better job vacuuming if I am in the pool rather than out of the pool. If your pool is still warm enough, try that but be very careful as you are walking around not to stir the stuff up with your feet and move the vac head very slowly.

Does the pool wall where the green is feel slimy? If not it may not be algae but possibly metal. Have you checked your copper and iron content?
Of course, if it feels slimy you are fighting algae.

Forgot to mention nothing is slimmy & the bottom is not slick at all. On Saturday morning i had 15.5 from 16 the nite before. Vacumed very carefully so not to put anything back into the water & gave it it's winter dose of polly so i had time to get the chloride back up. On Sunday had a few deposits in the cracks, vacumed them & stayed on top of the chlorine. This morning virtually had no deposits, chlorine was back up to par, did a quick vacume, dropped the water level, pluged & capped & put the coner on it. I have never had any problems with metals, i guess i'll find ou next spring. Thanks again for your help, i have never had anything like this happen & your system works great.