Review on Evo Dyne Pipe Cleaner (32oz): Made in the USA | Universal Piece Cleaning Solution | Safe on Glass, Pyrex, Silicone, Ceramics, Metals | Removes Tar & Resin - Soak and Rinse Formula by Cody Henry

35 minutes. If I left it overnight as the instructions suggested, I would have none of my metal pipe and bare glass pipe with no dots! It's NOT metal safe, it's NOT glass safe, it ruined a practically new tube as I've had the glass tube less than a month to determine the time between ordering and delivery. I wish I had never heard of this artificial pipe cleaner! EXTREMELY DISAPPOINTED! I spent money on mortar to destroy my pipes, it drove me crazier than a wet chicken! I wish I could give it NO STARS!