Is secondary pressure control important?

[SCMurphy]

It all depends on the back pressure. The system I have with bubble counters requires a higher pressure than system that just bubbles into the pumps and ladders. When I set up the second system I couldn't control the bubbles with my super deluxe needle valves until I lowered the pressure on the regulator. The bubble counters cause the original system I set up to have a higher back pressure.