Sorry I dropped the ball on this one,
SK. No worries--no caps is way better than all-caps.
Truthfully, any shark that's going to grow larger than 3' (and even those that don't) is going to be far easier to keep in the largest tank volume possible. Also, the shallower you can make this given volume, generally, the better.
I'll have to get back to you on the blue-dots, I know they don't do well, but I've misplaced "the rundown". I don't see why, as long as they don't outcompete the sharks, you couldn't have something like one of the great groupers, you would certainly have the space!
I'll suggest a search in our library, as well as Advanced Aquarist online
http://www.reefs.org/library as well as BobF's site
http://www.wetwebmedia.com (look in the marine aquarium articles section, and for ideas on larger systems, check out the aquatic business section as well).