How to Wash Gravel for an Aquarium The Spruce Pets
Place a large clean sieve, at least 6 inches across, over the bucket. Fill the sieve half full of gravel. Pour water over the gravel in the sieve, while gently shaking it. Rinsing the gravel over the bucket rather than over a drain allows gravel that slips through the sieve to be caught instead of going down the drain.