A small amount of Bloc-Aid used regularly in free-flowing drains will help prevent common sludge build-ups of grease, fats, paper, tobacco, soap scum, toothpaste, etc., that cause drains to become slow and eventually cause clogs. It is safe to use in garbage disposals, septic tanks and cesspools without harm to plumbing. The ready-to-use formula requires no mixing, simply pour into the drain