Blue and green light have shorter wavelengths than white light, and can penetrate through the water more efficiently making them look brighter. The human eye is more sensitive to blue and greens also which helps to make the lights look brighter.
However, if you do your boating in crystal clear waters we recommend White, as this simply enhances the natural beauty
All blue are great for slightly murkier waters .
Green which is great for attracting fish is the best colour for penetration in fresh water. If you do your boating in intercostal waterways or very bad visibility areas, green helps make the water look cleaner but is not always the most aesthetically pleasing.