Thank you for all the comments. Being new to this I'll have to decode what some of your comments mean.
I just downloaded Autodesk Eagle to see if I can create a wiring diagram to upload to the forum to help with the communication.
I'm using an external 9v power source through a LM2596S DC-DC Step Down Variable Volt Regulator Input 3.0-40V Output 1.5-35V Adjustable Buck Converter. 9v in stepping down to 6v. I'm using 6v to directly power the the pump and servo valves and using 9v to power the Nano which then powers the pressure sensor.
I'll look into getting some logic level N-channel MOSFETS
Do you have any experience with pressure sensors? I'm specifically hoping to find information on how to wire and code a pressure sensor that at a specified pressure it will trigger the air pump to turn off and open a vacuum valve. I'm thinking this would be a fairly common configuration but am not finding many resources that present information in a basic enough fashion for a beginner to understand.
Do you think I'd be better of using different pressure sensor one that doesn't have a breakout board?
Thanks for your perspective as they are much appreciated.