The patented design of the VorTech pumps places the motor outisde the aquarium which delivers the smallest in-tank footprint of any pump with the same flow rate. The external mounted motor also means that less heat is transferred to the water, which, in turn, means less money/energy spent on cooling. The VorTech pump creates a powerful yet gentle flow which eliminates dead spots in the tank. Easy installation thanks to its bracketless design with magnetic coupling. No electrical components ever touch the water which makes these pumps extremely safe. Controllable wave modes allow customisation for your unique tank set up. Creates a natural undertow along the sand bed, leading to a healthier ecosystem. Wireless capability enables coordination and enhanced functionality between multiple VorTech units straight from the box, with no extra equipment to buy - making it the most cost effective solution available. Specifications: Appropriate aquarium size: 2.5 - 50 Gallon Wattage: 8 to 18 Maximum aquarium glass thickness: 3/8\" Wet Side: 2.5\" diameter by 1.5\" long Dry side: 2.5\" by 2\" long Clearance required behind aquarium: 2.25\" Operational modes: Feed, constant speed, reef crest, lagoon, short pulse, long pulse, night, pump disconnect,EcoSmart Tidal Swell Mode