Kaboom® Bowl Blaster® is an entirely new way to clean the toilet that is fast, easier and more convenient then other toilet bowl cleaners. By simply pouring a capful of powder in the toilet bowl, the water-activated scouring foam rises to the rim and loosens the most resilient stains for you. Will I still need to use a toilet brush? For touch-ups and freshening, Kaboom® Bowl Blaster® does not require hard scrubbing; however, for deep cleaning jobs, a light brushing is recommended. Is Bowl Blaster safe on septic systems? Yes – Kaboom® Bowl Blaster® is safe for septic systems, plus with each bottle you can expect up to 15 uses. Will Bowl Blaster fight stains on the rim of the toilet? No, Bowl Blaster is designed to tackle tough stains below the rim; however, Kaboom® Shower, Tub & Tile Cleaner and Ultra Scrub® are two powerful cleaners that will remove untidy spots on the rim.