... , Water treatment, Aquarium, Fish Tank 2-Have different size Venturi 3-Best quality Venturi For Pool, Spa, Hot Tub, Water treatment, Aquarium ... TUB OZONINJECTION MAFIFLOD AND We have in stock other size venturi: 1- 1/4 inch $3.992- 1/2 inch $6 ... (but at a pressure lower than injector inlet pressure). These Injectors are extremely efficient. They operate only a minimal pressure differential ...