Help with Ballast Pump Issue

[Moon]

I own a 2003 MB Sports 220V that has 1600 lbs of ballast (hard Tanks). My problem is that the port side tank fills up automatically without me turning on the pump. The pump, from my understanding it is a Jabsco Junior Puppy (Systerm runs with no check valves). I know there aren't many people on here that own MB's, but I'm wondering if anyone has had a similiar issue? Is it possible that that there is enough force to allow water to flow to the tanks if the pump is bad? Also, I have changed out impellars and that did solve the problem. I would like to change both pumps to the Ballast Puppies, but I don't want to spend the money on the pumps until I know that changing them will solve my problem. Here are some pictures of where the pump and hard tank is located.