You’ve probably noticed that ships and boats have a different color paint job below the waterline. But if you’re anything like me, you’ve probably never questioned it.

However, this video answers the question, “Why are ships painted red below the waterline?” And the answer may interest you more than you thought it would.

It’s all to do with the worms and weed that can attach itself to the underside of ships. This damages the hull, and adds weight and drag.

So shipbuilders paint the underside of ships red with paint containing copper-based elements. These add an impenetrable barrier for problematic detritus.