Penn-Plax Small World Aquarium Air Pump & Filter Kit, 1 lb, for Tanks up to 5 Gallons

Penn-Plax Small World is an aquarium air pump and filter kit designed for tanks up to 5 gallons (18.9 L), with an Air-Tech AT2K0 pump and a disposable filter cartridge.

• Designed for tanks up to 5 gallons — suits small aquariums and habitats.
• Freshwater and saltwater compatible, with mounting for glass, acrylic, and plastic — works across common tank materials and setups.
• Disposable cartridge with carbon, zeolite crystals, and a Bio Sponge — combines chemical, physical, and biological filtration media.
• Air-Tech AT2K0 pump with silicone polymer flappers and raised rubber feet — built to stay in place during operation.
• Includes an air pump, air tubing, filter mount with connector, and filter media cartridge — the kit’s core components are together.
• 1 lb kit — identified by the product’s listed size.

This compact kit is made for keeping water moving and filtering aquarium water in smaller tanks and habitats. Its cartridge combines media for larger particles with carbon and zeolite crystals, while the pump supplies the airflow for the filter. It can be used in Penn-Plax Small World, New World, and Betta World habitats, as well as other compatible tanks.

What size aquarium is the Small World kit designed for?

The Penn-Plax Small World Air Pump and Filter Kit is designed for aquariums and tanks up to 5 gallons (18.9 L). It also suits Small World, New World, and Betta World habitats, and can mount to glass, acrylic, or plastic surfaces. The product is compatible with freshwater and saltwater setups.

• Maximum tank capacity: 5 gallons (18.9 L).
• Mounts to glass, acrylic, and plastic.
• For freshwater or saltwater aquariums.

How does the filter cartridge work?

The included Penn-Plax cartridge combines carbon and zeolite crystals with a Bio Sponge for multiple types of filtration. The carbon and zeolite media absorb ammonia, nitrites, nitrates, and phosphates, and are intended to help remove harmful chemicals and toxins, reduce discoloration, and lessen foul odors. The Bio Sponge captures larger particulate matter and supports the colonization of anaerobic bacteria for biological filtration.

• Carbon and zeolite crystals provide chemical filtration.
• The Bio Sponge handles larger particles and supports biological filtration.
• The cartridge is disposable and should be replaced every 2–4 weeks for best results.

What comes with the kit, and how do I prepare it?

The Penn-Plax kit contains an Air-Tech AT2K0 air pump, air tubing, a filter mount with connector, and one filter media cartridge. The pump measures 3 × 2 × 1.75 in (7.62 × 5.08 × 4.45 cm); the filter mount with connector measures 1.5 × 1.25 × 5 in (3.81 × 3.18 × 12.7 cm); and the cartridge measures 1.3 × 1.1 × 4.1 in (3.30 × 2.79 × 10.41 cm). Before placing the filtration unit in the tank, briefly rinse it with warm water to remove carbon or zeolite dust. Skipping this step can initially make the water look dark or cloudy.

• The pump has a strong motor, silicone polymer flappers, a thick cover, and raised rubber feet.
• The pump is designed for quiet, efficient, reliable operation.
• Rinse the filtration unit before installation; replace the disposable cartridge every 2–4 weeks.

This kit is suited to aquarium owners setting up a small tank or habitat who want an air pump and a cartridge combining chemical, physical, and biological filtration media. Its 5-gallon capacity limit and compatibility with freshwater and saltwater setups make it a defined fit for smaller aquariums.