This sprayer is what I use. It is different than most on the market. It develops a fine even spray pattern while holding pressure within the line. A fine spray that covers the entire top surface of the growing medium is very important. Adding the most oxygen to the feed as possible before the feed enters the root zone is very important. Holding pressure within the feed manifold allows more plants to be fed per pump. The cost of these little guys is worth it.
These sprayers have threads on them. Make your manifold ring first, then locate the top of the ring and make small holes in the ½ inch vinyl tube. These holes will be where you are going screw in the sprayers. Make sure you make the holes on the top or crest of the ring. If you don’t they will point up or down and your spray pattern will be going down to the growing medium or shooting into the air.