Black dirty patches on bottom of pool

[Dave S]

I have black dirty patches on bottom of pool.
Is this Black Algae?
My pool is the pebble finish.

Have just bought an auto matic cleaner and have put up with
silt and stuff on bottom of pool for 9 months. Though it would go away after auto cleaner purchase.

Should I shock my pool? and what is the best way
to keep this possible black algae away?

[jim]

try a sodium bromide mix to control black algae

buy about 2 pounds...and pour it right in.. powder...as close to ontop of the algae as possible..

let it sit for 3 hours or so..

do not turn on the filter

then dump in huge amounts of shock... like.. four or times what you normally would put in....

let it sit overnight.. and scrub .....if possible...