It may be too late in the day, but I figured I would save you the time of testing the system on the water, as it's simply not going to work (for the reasons pointed out above).
Here are some basics for aerator (the class of pump the Tsunami belongs to) based system:
- Never use a scupper intake, all it will do is lead to your bags filling whenever the boat is driving
- Your fill pumps need to be installed below the waterline as close to the thru-hull intake as possible
- You need to use vented loops to prevent water from entering or exiting the bags passively
- Drain pumps need to be installed at or below the level of the bottom fitting on the bag, and should be as close to the bag as possible (we prefer that our customers connect them directly to the bag, quick connect fittings can be used).
Because aerator pumps are not self-priming (they are not capable of generating negative pressure on the supply hose to the pump) they'll never work correctly if installed above the water line for filling, or above the bottom of the bag for draining.
There's more info on the basics of setting up system on our Ballast Blog
, and we're always happy to answer questions.