Gaz is right!! The pica pica showed up in the last two weeks of March this year. They are usually from 15' to the surface, right where we all spend 3mins.Sunscreen is your best bethowever I have not tried the new product mentioned on this thread. If you do get munched try windex, meat tenderizer or vinager. the nasty little bumps will go away in a week to ten days in my experience.also I'm not sure if you can see pica pica but the day I got hit this March there were what I would describe as tiny (the size of a ballpoint pen head)urchinlike things suspended in the water, I illuminated one on my dive light.Safe diving!