Liquid-Plumr’s thick gel was specifically designed to power through hair clogs that slow down sink, tub and shower drains. According to the manufacturer, it is septic-safe, and based on our experience with other Liquid-Plumr products, we have no reason to think otherwise.
Just consider the application before using this product to clear up any old drain issue. “This one is an oxidizing cleaner, so it’s very tough on organic matter like hair and food, but less so on grease,” says Rachel Rothman, chief technologist at the Good Housekeeping Institute.
Per instructions, wait for all the water to drain out of the sink or tub (or bail it out if it won’t flow), then pour the bottle of Liquid-Plumr — yes, you need to use the whole bottle — slowly down the drain. It takes at least 15 minutes to work. For badly clogged drains, you can leave Liquid-Plumr in the drain overnight to work, then flush thoroughly with hot water in the morning.
Like Drano, this product is unscented and mild. Even self-reported sensitive users say there aren’t any bothersome fumes to contend with when using Liquid-Plumr.