It covers 800 square feet of surface area. sent me the white at my request. If just spot painting, perhaps you can shade the areas, with small tables or something to block direct sun, if thats an issue. We can also perform dye testing to find out . probably interested in is called WATER GARD 300, You can purchase it online at that it can be applied underwater and the issue is something unique to Just what I was looking for. (CLICK HERE),