Nope. I am getting a bunch of black caps.Will you have valves on each outlet to balance the flow?
Basically, I drill them with a step bit starting with the smallest hole at the far end and gradually getting bigger. I can swap out caps as I see fit or totally remove them. Another thing to do is heat a short piece of pvc and turn it into a nozzle by pinching it. This can adjust the flow as well.
The reason for this is expense and looks. I want it to blend in as much as I can and still keep the manifold on top of the aquarium for easy access. Plus that many true union valves would get expensive.
I did one of these on my 240 and worked perfectly. I ended up with one pinched nozzle, 4 caps with holes of different sizes and one totally open.
Now, the only caveat to this is, once you drill a cap larger, you can't go back so it is a waste. But, even buying the caps in black, they aren't expensive.
I will try it completely open at first and feel the flow coming out and see where it needs help. Keep in mind, I only shoot for 4 or 5 times turnover per hour so there won't be much flow at each outlet to begin with. It's all about distributing the filtered water and letting the power heads create flow. I can force more through if I decide to later on and adjust the caps.