What kind of pumps are they? From your description I'm guessing diaphragm
pumps. If so, that may be how they will pump
, depending on the design. If one large diaphragm
and one pair of valves (one in, one out) then by the nature of the pump
the output will pulse.
I have a Jabsco
diaphragm pump that has a multisection diaphragm is essentially four small pumps running off the one motor
so the output is much smoother. An impeller type pump would also give a smoother output.