Clogs are held together and cause the buildup in pipes by gunk called biofilm. ... But when biofilm builds up all along the drain pipe, liquid drain cleaner can only affect the biofilm that the solution will reach and not the entire pipe or drain. When unclogging laundry drains, a liquid drain cleaner will never work.

How effective is drain cleaner?

The advantage of using chemical drain cleaners is that they're powerful and effective almost immediately. However, the chemical fumes are toxic; they can burn your eyes, eat through clothing and damage drain traps.

Why you shouldn't use drain cleaners?

They're Dangerous for You & Your Family

Drain cleaners are often acids with the potency and dissolving ability of things like battery acid. Battery acid can cause severe burns and even permanent disfiguration if you're exposed to it for too long.