If you have to disconnect hoses with any degree of regularity, you should consider Quick Disconnect couplings. They provide fast, positive, leakproof connections for air, liquids and dry products. They connect and disconnect in seconds without tools; simply lift the cam levers. The female fittings use a Buna-N gasket where they meet the male fitting for a cushioned, leakproof seal.
Black fiber-reinforced polypropylene is designed for most aquaculture applications. The polypropylene is rated to 100 psi on 3/4" to 2" size and 50 psi on the 3" size at 68°F (20°C). Order 10+ fittings (may be mixed) to qualify for a 10% discount.