hi I have a 03 55 dancer. I’ve been noticing water in my mid ship bilge, which is located in the rear stateroom. After going through all the systems, I have a main drain pipe that my midship bilge,shower sump, floor hatch drain and AC discharge all utilize. When my ac pump is on I have good flow exiting the boat but I have a backflow thru the midship bilge piping. I have flushed the discharge pipe out thru the mid ship bilge and I have good flow. I have changed the check valve in kind with the whale duckbill type and it hasn’t solved the problem. I ordered a more rigid type of check valve but was wondering if anyone had a similar issue or a suggestion to stop the back flow into the midship bilge? Thanks.