Sean your tank is simply amazing! I looked at your link to the SA Marine forum to see the construction process and spent about two hours reading and looking. Wow!!!! I've done concrete work and that was no small effort, fascinating though. And I can't get over what you have to go through to do water changes! OMG.
Your tank is truly an inspiration, though and I like the piece of artwork you had made above it too. It makes me want to come to SA just to see your tank! What a beautiful little slice of ocean you have there. 8)