- 1). Take the rocks you plan to use in your aquarium and place them in a bucket of warm water. Allow the rocks to sit in the water for at least a couple of days to remove any surface dirt and other impurities.
- 2). Remove the rocks from the water, allow them to dry and then submerge them again. Change the water one more time and rinse the rocks off again. Use a scrub brush to remove any additional dirt from the rocks.
- 3). Fill a bucket with a solution of bleach and water, then submerge the rocks in that solution and allow them to soak for at least a couple of days. If you do not want to bleach the rocks you can place them in a large pot and boil them on your stove or grill.
- 4). Dry the rocks completely before you place them in your aquarium. Make sure that all dirt and contaminants have been removed before placing the rocks in your aquarium.
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