Aspen Aeration 1/2th Hp Complete Aeration KitsThis Complete Kit for 1. 5 acre ponds Includes a 1 2Hp Rocking Piston Air Pump in a cabinet, a 3 way manifold with a pressure gauge, three 100 ft rolls of 3 8" weighted tubing, and three 9 inch diffusers with bases The manifold includes an attached is a pressure relief valve which opens at approximately 25 psi to prevent damage to the compressor The self weighted air hose is very heavy duty and pliable. It is stronger, thicker and heavier than other