Applied Biochemists Silvertrine uses the power of elemental silver to quickly and effectively kill off tough black and mustard algae growth as well as algae slime. Its formula coats the floor and pool walls with a residual that continues to fight growth after treatment. The non-staining formula treats twice the volume of water as other silver algaecides, so you use half as much. Silvertrine is tasteless, odorless, and non-foaming at pool concentration. Best of all, Silvertrine is made by Applied Biochemists, a leader in bio-based pool chemicals, allowing you to buy with confidence.