It may not flow enough. I don't do fish. But I bet one of the ind. supply houses has a needle valve that will flow enough.

I used to have a car with a vac switch that killed the a/c compressor at very low vac, like wot runs, but of course, that won't work on a forced induction motor. Maybe a Hobbs pressure switch to kill it at high boost?

Not responsible for advice not taken...