I read this on the old forums.

Can you get in the pool yet? If you can reach down and feel the "lines of stuff". If it is gritty it is sand or dirt. If it is slimy it is algae.

If it is algea you need to shock the pool. Depending on you Stabalizer level raise the Chlorine to the appropriate shock level. Keep it at that level for several days and the algae should go away.

Can you post your current readings? In particular a Free Chlorine and a Combined Chlorine Level and a Stabalizer Level. PH and Alkalinity would also be helpful.