Mazzei fertilizer injectors are commercial-grade, Venturi injectors with no moving parts to wear out or break down. They work by suction, and can draw liquid fertilizer from virtually any container. The Mazzei can be plumbed on a bypass for less restriction (the preferred method), or directly into a main water line.

You will need to experiment to get the dosages required, but once operating, the Mazzei is incredibly reliable and relatively maintenance free.

Important Note:
If taking apart the Mazzei injector for cleaning, be careful not to lose the spring or ball inside the injector.