The PRO-Line Aerated bottom drain has a solid 1-inch air feed and at no point requires you to use flexible pipes to connect air inside the drain; just simply connect 1 inch pressure pipe to the side of the drain and run parallel to the main 4 inch drain pipe.     

• The highest quality 250mm Gummi 'Jager' diffuser.      
• Uses a 1" air feed directly to the diffuser, eliminating flexible pipe.     
• The diaphragm can handle 150 litres; we recommend between 40 - 80 litres. This will also depend on the backpressure and the depth of the pond.      
• Available with or without a liner flange kit       
• Includes a 1" direct air feed connector (for the end of the 1" pipe).