In general, river rock is quite porous, and will need to be sealed when laid down and resealed every two to three years thereafter to protect the integrity of the surface and prevent staining and molding.
-
Clean and sanitize the rock. Mix a four-to-one mixture of water to bleach in a large bucket, and apply the solution liberally to the river rock surface with a paint brush or sponge. Wear rubber gloves throughout this process. Allow the mixture 30 minutes to soak into the rock, and then rinse completely with a garden hose. Leave the surface to dry for a minimum of two days.
-
Apply one coat of rock glaze sealant with a paint roller, following the manufacturer's instructions. Allow the sealer to dry thoroughly.
-
Apply a second light coat of the sealer once the first coat is dry. Allow the river rocks to dry and cure completely for at least 48 hours, or 72 hours for driveways.