This came from a conversation that I had with wicked, and I'm sure many of you have thought about this. But how about on the back of the T-shirt something like:
(A picture of an officer)
Caption: "I promise officer, it's not what you think, it's a saltwater tank!!"
OR OR
(A picture of an officer kicking in your door)
Caption: "only in the "reef" hobby"
HAHAHAHA, late night rambles!!