The Reef-Ready Aquarium is equipped with a MegaFlow Overflow system that is engineered to allow maximum water flow to the main filter system while greatly reducing cascading water sound. The Aqueon Overflow system design includes multi-level water intakes, providing more effective circulation and filtration and eliminating dead water zones in your aquarium. The Overflow Accessory Kit also comes with the aquarium that includes: adjustable drainpipe, nozzle, dual nozzle, return pipe, 3/4" elbow, 1" bulkhead, 3/4" universal, 3/4" bulkhead, air intake elbow, 90° elbow, drainpipe base, strainer and bulkhead wrench. Limited Lifetime Warranty.