Filters

Fish Tank Filters

Properly functioning fish tank filters are critical to the health and safety of your fish. Which is why, at PetSmart, we offer so many options for tanks and aquariums of every size. The best filter for your fish tank depends on its size, water type, substrate and species of fish, invertebrates and plants that live there. Filters are necessary to remove solid wastes as well as chemical contaminants created during the nitrogen cycle. Even if the water looks clean, invisible toxic chemicals can still be harmful and should be removed or converted to less harmful chemicals by beneficial bacteria. We carry filters that combine different methods of filtration to fit any need. Mechanical filtration relies on water circulation to strain loose particles of food and waste floating in the water, usually with a sponge or other media that can be cleaned or replaced. Large marine reef tanks or other saltwater aquariums with a wide variety of inhabitants can benefit from protein skimmers that agitate the water to break up organic compounds and lift them to the surface of the water for removal by the protein skimmer. However, mechanical filters do not remove harmful chemicals, particularly ammonia, nitrite and nitrates, which are toxic byproducts from fish waste. Chemical filters use activated carbon (charcoal) to remove dissolved particles and harmful elements in the water. Biological filtration is filter media that allows beneficial bacteria to thrive by protecting it from strong currents while still allowing food and oxygen to flow through. Large particles need to be removed by the mechanical filtration to avoid clogs that can kill the bacteria. This friendly bacteria converts oxygen, fish waste and harmful chemicals like ammonia and nitrites into less toxic nitrates. These nitrates are then removed by water changes and even live plants. You may want to upgrade your filtration system if you decide to add more fish or move up to a larger aquarium. Under gravel filters use a basic mechanical process that rely on pumps to circulate the water into the substrate for cleaning. Aquarium power filters, also called hanging on the back (HOB) or external overflow filters, are included in most aquarium kits. Canister filters are best suited for large tanks. Canisters sit outside the tank and provide all three levels of filtration by forcing water through the filter media, which may contain activated carbon and a place for beneficial bacteria to live. With high-quality canister, underwater, undergravel and power filters, plus replacement parts and accessories, you can find everything you need in one place to keep their fish tank clean and the water clear. Browse our newest selection of fish tank filters from top-rated brands.