There is the bane of having to pull the boat, scrape, sand and paint for hours on end and having to buy paint that seems excessively expensive for what you are getting. However, if you have ever tried to get barnacles off a bottom that has been left in the water without bottom paint, you will realize also what a boon it can be. After 25 years have passed my daughter still complains about the hours she worked cleaning the bottom of our houseboat. While most houseboaters do their houseboating in fresh waters and do not have as great a problem, those who live on the coasts are well aware of the problem of bottom fouling and the need for bottom paint. The most common bottom paints are those containing copper.
Copper is a most effective way to prevent bottom fouling.
The old system of sheathing wooden boats with copper sheathing was highly effective and boats that had the copper sheathing could go for years without accumulating any significant fouling. Unfortunately, we do not have that luxury now and have to depend on paints containing copper to do the job for us, unless you have an aluminum boat, and then you need a tin bearing paint. Copper paints are used on wood, steel and fiberglass boats and come in many different compounds. There are paints for racing, paints for hulls that rarely move, paints designed for boats that are pulled regularly and paints designed for boats that have longer periods between haul outs. If you were to pull your boat at the end of every day, you probably would not even need bottom paint and there are many folks trailering boats that never use one.