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Uses for Baking Soda in Aquariums

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Baking soda provides several benefits to aquariums. The versatile nontoxic compound can clean and deodorize an aquarium without risking harm to the tank’s inhabitants -- though you must remove the fish before you start to clean. Baking soda also can serve to adjust the pH of aquarium water in an aquarium, rendering the environment more suitable for fish and other occupants.


Baking soda is common name of sodium bicarbonate. This compound starts as soda ash, something that occurs naturally. It may be mined or it may be manufactured from table salt, ammonia and carbon dioxide. The soda ash is then dissolved, and carbon dioxide bubbles are forced through the solution. The result is sodium bicarbonate, a pure, natural substance that can put out fires, raise dough during baking, brush teeth without scratching them and treat acid indigestion.


Baking soda works two ways to clean an aquarium. If you soak a dirty aquarium with a baking soda solution, it will break down dirt and greasy substances clinging to the surfaces. On a damp sponge, baking soda is abrasive enough to remove grime and stubborn algae clinging to glass but is gentle enough not to scratch. A simple rinse and the aquarium is ready to be put back into service.


Baking soda's powerful deodorizing ability combined with its nontoxic nature make it ideal to get nasty smells out of an old, stagnant aquarium. Rinse out the aquarium using a solution of a quarter-cup of baking soda with 4 cups of water. If the smell lingers, fill the aquarium with a solution at that strength and let it stand overnight before rinsing. Gravel and decorations inside the aquarium will benefit from the baking soda; leave them in but rinse them well before returning your fish to the tank.

Water Adjustments

The pH level is vitally important in an aquarium; a pH that's too low means the water is acidic; the fish in the tank may die. Adding baking soda helps to neutralize the acidic properties of the water and raise the pH to a safer level. This compound is best for making small adjustments to the pH and ideally in situations where only minute changes are required. The changes, while small, do happen rapidly, ideal for the aquarist who needs to make a quick adjustment to the pH of a tank. But be warned: Drastic changes will kill fish more readily than moderately acidic water conditions will.