BS”D
Drano is best left for kiddush. It is a total waste of time and a very dangerous chemical to boot. Just reminds me I haven’t made harif in ages and I’m going to pick up some Sano-installator with a Badatz hechsher to use instead of salt with the peppers and tomatoes.
Sulfuric acid has no business in the home unless you happen to be a trained professional. In most states, acid drain opener “Hercules Clobber” can only be sold to licenced plumbers.