Bottom paint is one of those things that people only seem to think about when they are on the hard. When the boat is wet, the bottom paint is hidden beneath the waves and forgotten from all thoughts.
This is probably a safer way to think about bottom paint, as the alternative is to research and compare all different types and formulations to see which works best. Research is largely a waste of time since the amount and type of growth you will develop is particular to where you are. Where you are is not as diverse as a general area, and if a study was performed in your same general vicinity, the water qualities might be slightly different and the growth you will develop will also be different from where the study was performed.
Your next option is to try out every single bottom paint that exists. This would be a very long study, as bottom paint tends to last for at least one year. Basically, you would paint the bottom and give it a shot. Next year, you will choose a different paint and try it again for a year. The following year, you will try another paint. At the end of a lifetime, you will find that the paints you tested in the beginning are no longer available and your data is irrelevant now.
The other option is to ask around and buy the cheapest option. If you move your boat often, CPP from West Marine is a good option. It is labeled as "house brand" but is actually manufactured by Pettit, a maker of high quality bottom paints. This cheap paint has enough copper in it to keep growth from taking over your bottom. A lot of cruisers use it on their bottoms, and they all say it works great as long as you keep moving. If you sit still for a few weeks, a layer of slime will develop that will rob some speed. This thin layer can be easily removed with a brush or a scrub pad, renewing your bottom to a smooth slick machine!
Windpuff was painted in April 2015 with one coat of West Marine brand CPP.
Twenty months later, Windpuff was pulled out of the water to be put on the hard while we go cruising. The bottom wasn't that horrible, considering that we haven't moved Windpuff in a while. There were a few barnacles here and there, and the bottom was covered in a thin layer of slime that wiped away easily.
I'm not saying that CPP from West Marine is the best bottom paint ever, but I am saying that it does the job and it's cheap!
