Is this a glass tank?
the pump may pump 400gph at 4' but then you have to add in friction and angle loss. The length of tubing/pipe used will reduce the head and well as every angled fitting you put in... you won't end up with 400 gph if you are only calculating in the head loss.
Very similar to what I have on the SH tank.
Cookie Press Shortbread
Prep Time: 25 Minutes
Cook Time: 10 Minutes Ready In: 35 Minutes
Yields: 24 servings
INGREDIENTS:
1 cup butter
1 1/2 cups all-purpose flour
1/2 cup confectioners' sugar 1/4 teaspoon vanilla extract
1/2 cup cornstarch
DIRECTIONS:
1. Preheat oven to 350 degrees F (175 degrees C).
2. In a medium mixing bowl, cream together butter, confectioners' sugar, and vanilla until smooth with electric mixer. Stir in flour and cornstarch. Pop dough into your cookie press, and away you go! Press cookies out onto ungreased cookie sheets.
3. Bake for 8 to 10 minutes in the preheated oven, or until the peaks are golden.
4. Send some to Renee. :-)