I normally stay away from chemical drain cleaners, preferring to use a snake. I had a slow draining kitchen sink in a home with 1970 vintage galvanized plumbing. The piping was partially blocked with rust, and, the genius builder ran the drain pipes under the concrete slab. Replacement would be expensive. I was able to clear out some of the loose rust with a piece of 1/2 inch pipe duct taped into a shop vac hose. I snaked the line several times with no improvement in flow. I did pull out a lot of hair and other crud.
I went to a local hardware store for a gallon of conventional lye based drain cleaner. The hardware store guy said he had something way better. He sold me a quart bottle of Rooto drain cleaner. This stuff is concentrated sulfuric acid. Safety goggles and gloves are required with this foul smelling brew. I dumped the entire quart down the drain and waited five minutes, per the instructions.
I now have a free flowing drain for 12 bucks! This stuff works, but, handle it with care.
I went to a local hardware store for a gallon of conventional lye based drain cleaner. The hardware store guy said he had something way better. He sold me a quart bottle of Rooto drain cleaner. This stuff is concentrated sulfuric acid. Safety goggles and gloves are required with this foul smelling brew. I dumped the entire quart down the drain and waited five minutes, per the instructions.
I now have a free flowing drain for 12 bucks! This stuff works, but, handle it with care.