Beananimal uses three valves, which you only need one. One restricts flow to just the point of constant siphon (so the pipe has no air at all). For pipes, this is the maximum flowrate a pipe of a given diameter can support under gravity feed. Siphons are quiet. The other flow is trickle flow and last one is emergency drain. I am sure you know all this. As for overflow, I like coast to coast style, but that is just me. If you check on RC or NCRC, I have some pictures of my coast to coast I built with plastic from tap plastics. Then I just had to drill holes and fit them inside my tank with bulkheads.