Water is definitely not a friend for materials such as metals, electronics, wood, etc. For example, when metal is submerged underwater it increases the rate of corrosion of the metal (i.e steel). So we must consider how we can fight against these negative effects the water produces against devices that are made for the water like boats. There are metals out there that are able to neglect the negative attributes of water; however some of us may not have the money to spend on corrosion resistant steel. So what has been done is to create a coating that could be placed over the metal to act as a layer to protect these metals.
There are many coatings out there today however each of these coatings may serve a different purpose. When developing vehicles or devices for underwater purposes it is important to choose a coating that provides cathodic protection. Cathodic protection is used to prevent the metal from being corroded and is usually cheaper than straight out buying corrosion resistant steel. These coatings do come in different colors so you could alter the color of the metal to your choosing. If you are worried about meeting certain specifications no need to worry. There are coatings that go through testing to ensure performance. For example, a coating called Alocit made by A&E Group was tested by the navy and it is 1 of the 3 that meets the specification for the US Army Corps of Engineers! This coating provides great resistance and adhesion. The best part about this and other coatings is that the installation is simple!