hello everyone im newbie, my problem isi have what looks like black sand on the bottom of pool( marsite)that wont brush away . finish is 11 years old.starting to go up the sides .this all started about 4 months ago thanks
Can you scrape it off? If so what does it look like?
Try holding a trichlor tablet on it a little while. If it lightens, it's organic.
If it doesn't lighten with a trichlor puck then try crushing some vitamin C tablets and putting them in an old sock and holding them on it for a little while. If that lightens it then it's metals.
Then raising and keeping the FC above normal level for a while will probably lighten them. It may take a while for it to make a big difference but it should.
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Welcome to TFP! For a wealth of pool care information please check out our free Pool School. If you are in need of specific help then we encourage you to Register and ask us here in the forum!