I am in the process of installing a new ballast system in my boat. I was wondering could I just ground pumps to engine and just run positive to switches? <BR> <BR>I am using aerator pumps, and with the pumps being mounted below engine. this would cut my wiring in half. <BR> <BR>Thanks in advance for the help.

Are you using relays?

No, they only draw a few amps.

yes you can ground to the engine

^^^^ 2nd that