What I did was take the vent line from the 1100 and run it to bottom fill on 400 then put a new vent line from top of 400 to check valve then to vent on boat, check valve is to help empty the piggy back set up but even with then we tend to empty while moving with bow high sometimes even while I am surfing it's kind of a game to see how long I can go for.

Sent from my SM-T330NU using Tapatalk