16mm Aquarium Plastic Filter Bio Balls (50Pcs)
50 pieces of plastic bio balls for creating biological filtration within your tank. Place in a sump, external, or hanging filter to grow nitrifying bacteria that naturally converts ammonia and nitrite. Clean every so often when you regularly do a water change and rinse in aquarium water as tap water can kill bacteria.
These can be used with both saltwater and freshwater tanks. In general, 2.2 gallons of bio balls to 100 gallons of water is the recommended amount needed for maximum filtration.
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