Just regular spray paint. Just dont rub sharp things on the back.....It WILL scratch off. But nothing you cant just touch up later. If you have a lot of HOB stuff.......paint and then put paper over the paint to protect it. I just painted mine.......but there are little spots from my old HOB filter that got rubbed off. I want to paint mine DEEP blue almost black. Simulate deep water as much as possible. Mine is black though, which makes colors pop real nice. :)