Thought I had bottom staining figured out this year. I use a ceramic coating on my boat. With all the claims of Nothing sticks to ceramic coatings or at least wipes off easily. Nope didn't happen. Spent six days on vacation on a lake with slightly stain water, you can see down 4 to 5 ft. After the fifth day I noticed discoloration on the side and bottom of my boat. I got in the water and wiped off what I could, but when I took my boat out of the water there was still a light staining. Had to do a full cleaning when I got home. Also know a boater that spent a big chunk of money to have his boat professionally ceramic coated and the bottom of his boat is badly stained. So anyone thinking to have a ceramic coating put on there boat to prevent staining you mite want to save your money. On the good side anything else does wipe off easy. Both boats are Fiberglass hulls. I get no staining or discoloration on day trips.