North Coast Pets has all your necessary aquarium supplies for the reef aquarium, even the uncommon stuff like ball valves. Ball valves have many uses in the reef aquarium. Use them to control the water into or out of a pump. Use them for an emergency shut off. Every pump should incorporate 2 ball valves and 2 unions as shown below. This is done for flow control as well as ease of removal if the pump needs to be serviced. These schedule 80 ball valves are not like the schedule 40 valves that you see in the hardware stores. These valves are super smooth operating for superior control. Photos below show ball valves in use. Note the pump using both ball valves and unions. A ball valve should never be placed on a pump's input to control water flow. Always use a ball valve on the pump's output, not the input, to control water flow. This will prevent burning out the pump.
