Shade
Monster Junkie
You are correct. I got my abilities confused. 
How's this?
Crushing Blow (Ex): As a full-round action, an umibozu can set up vibrations within the hull of a boat, then smash the vessel to splinters. The ship is hit automatically, taking slam damage. The ship's pilot must make a Reflex saving throw (DC 20) after each hit to keep the vessel from being breached and sinking in 1d10 minutes. Apply a modifier to the DC based on the type of ship: rowboat +4, keelboat +2, sailing ship or longship +0, warship -3, galley -5. Regardless of the ship's saving throw result, characters aboard the ship must make Reflex saving throws (DC 20); a successful save means the character takes 1d4 points of damage; on a failed save, a character on deck is hurled overboard and a character belowdecks takes 2d4 points of damage.

How's this?
Crushing Blow (Ex): As a full-round action, an umibozu can set up vibrations within the hull of a boat, then smash the vessel to splinters. The ship is hit automatically, taking slam damage. The ship's pilot must make a Reflex saving throw (DC 20) after each hit to keep the vessel from being breached and sinking in 1d10 minutes. Apply a modifier to the DC based on the type of ship: rowboat +4, keelboat +2, sailing ship or longship +0, warship -3, galley -5. Regardless of the ship's saving throw result, characters aboard the ship must make Reflex saving throws (DC 20); a successful save means the character takes 1d4 points of damage; on a failed save, a character on deck is hurled overboard and a character belowdecks takes 2d4 points of damage.