I have 2 gallons of the Pettit Protect barrier coat. I will be putting this on the bottom of my Catalina 22. Using the calculations, I figured that the bottom of the boat is about 140 Sq ft. Each 1 gal of Pettit Protect covers about 225 sq ft. With 3 coats that is a need for about 420 sq ft and it comes out to 450 sq ft of Pettit. That is close. Has anyone ever used the Pettit Protect and will 2 gallons be enough to cover the bottom fully with 3 coats?