Model AW700: You want air, not hassles with air pumps! One of the BEST air pumps in the industry. For aquariums up to 55 gallons. Dual air outlets provide enough air power to run up to 6 airstones, filters or air-operated ornaments in deeper aquariums. Easily converts to a single air outlet with the T-connector provided. Tricker's BEST selling air pump for an aquarium.