I am new here, but I'm in dire need of help for my father's pool. We just opened it up yesterday and this is what we found. Pool stores are no help and we are baffled. We just had the liner installed last year and are worried it is not fixable. Its only on the walls of the vinyl. Thanks for all the help.
Never seen before.....black algae?
- Thread starter shadygrove911
- Start date
Welcome to TFP!
The first step is to SLAM Process the pool to kill the algae as shown here, SLAM Process. Then you can work on black algae if itmexists. More here, Pool School - Black Algae
The first step is to SLAM Process the pool to kill the algae as shown here, SLAM Process. Then you can work on black algae if itmexists. More here, Pool School - Black Algae
I would brush and SLAM that pool every day til your arms fall off or it clears up... which ever comes first. 
It does look like black algae. There's mustard algae on the slopes and floors.
It's odd that it's only on the walls.
Sometimes certain organisms grow beneath the liner and exude chemicals that leach through the liner.
Vinyl Liners: Tackling the Toughest Stains of All, the Kind Behind the Liner| Pool Spa News | Maintenance, Quarterly Market Reports
It's odd that it's only on the walls.
Sometimes certain organisms grow beneath the liner and exude chemicals that leach through the liner.
Vinyl Liners: Tackling the Toughest Stains of All, the Kind Behind the Liner| Pool Spa News | Maintenance, Quarterly Market Reports
Sounds like the absolute worst possible scenario....
. I have been brushing a couple times a day and it is definitely improving. I working on it now with chemical, fingers crossed. I just cant figure out why it is only on the walls and that is it. The floor and water are clear now, everything looks great except for the walls, which is really making me worry that you are correct.....I am literally praying right now that this is not the case, considering the liner is only a year old.