InVade Bio Bullet will not harm Septic systems or tanks.
InVade Bio Bullets are ideal for placement in urinals, soda fountain and beer tap drip trays, condensation pans, or on top of floor drains that are concealed under counters, etc. They are not labeled for use in any type of aquatic areas like freshwater lakes where there is aquatic life like mussels.
InVade Bio Bullet can be placed on top of floor drains or can be hung inside the drain itself if you can remove and tie with twine or string to the drain cover so water flows over it.