Which filter medium is commonly used to remove dissolved chemical contaminants from aquarium water?

Which filter medium is commonly used to remove dissolved chemical contaminants from aquarium water?

• A. Biologic
• B. Mechanical
• C. Chemical
• D. Activated carbon

Answer: (D)

Activated carbon works by adsorption, meaning dissolved chemical contaminants in the water stick to the porous surface of the carbon and are removed as water passes through. Its enormous surface area lets it capture a wide range of substances many aquarists want out of their water—chlorine and chloramines from tap water, dissolved organics that cause odors and color, tannins from decaying plant matter, and various medications or additives that may enter the tank. Because of this broad, non-specific removal capability, activated carbon is the go-to filter medium for addressing dissolved chemical contaminants. Keep in mind it doesn’t remove dissolved minerals or every inorganic contaminant, and its capacity can be exhausted with use, so it needs periodic replacement or regeneration. Other media focus on different tasks: biological media support beneficial bacteria for the nitrogen cycle, mechanical media trap particles, and chemical resins target specific contaminants, but activated carbon provides the broad, general removal of dissolved chemicals.

Activated carbon works by adsorption, meaning dissolved chemical contaminants in the water stick to the porous surface of the carbon and are removed as water passes through. Its enormous surface area lets it capture a wide range of substances many aquarists want out of their water—chlorine and chloramines from tap water, dissolved organics that cause odors and color, tannins from decaying plant matter, and various medications or additives that may enter the tank. Because of this broad, non-specific removal capability, activated carbon is the go-to filter medium for addressing dissolved chemical contaminants.

Keep in mind it doesn’t remove dissolved minerals or every inorganic contaminant, and its capacity can be exhausted with use, so it needs periodic replacement or regeneration. Other media focus on different tasks: biological media support beneficial bacteria for the nitrogen cycle, mechanical media trap particles, and chemical resins target specific contaminants, but activated carbon provides the broad, general removal of dissolved chemicals.