Very funny, edgy, and adult oriented! MD has had a cool clean up crew at work shirt. I also have a shirt from Incredible Corals that I like. It's a circle logo with their name and a coral in the center. And I have about ten or twelve shirts from our MACNA in DC last year. For me, it's really in the graphic design that it looks good and is fun to wear. I think all the shirts out there convey the reefing message. Considering Origami's posts above, I think a great place for a rough draft would the Capital building with both wings. You could do a lot with the pillars and ornate structure being rockwork with fish hiding in and around pillars and such. Add a starfish. Maybe some political humor around what the aquarium inhabitants are doing since it's a Presidential election year. Just random thoughts off the top of my head.