Aqua Illumination Nero 5 Powerhead (3000 GPH)Small, Powerful, and Smart! Max Flow 3000 GPH Aqua Illumination's Nero 5 creates an adjustable broad flow that is strong but gentle at the same time. Traditional propeller designs produce a hard stream that can irritate corals where the Nero 5's innovative propeller pushes water in a wide pattern that can move foods, detritus, or other free floating particles around without blasting corals directly. Powerheads have many different uses around a reef