Reeferdude: Here's my .02. Hope I dont burst any bubbles.
Sand tigers- Your right about their size, and they are also very temperamental. I would not even consider one in less than a 10-15k tank.
Bonnetheads & Black Tips: I think either of these would make a great addition to your tank. I personally would get one or the other though, not both. They are both very flighty, meaning they get startled easily and may even startle/harrass each other. Both of these sharks are also very active (eat alot) and would require 2x the filtration.
The tank size you are planning is huge, but IMO neither it or my tank for that matter, will be big enough to house a full grown requiem shark.
I know what web site you are referring to. Dont waste your time searching for it because they went out of biz. When your ready for the sharks, let me know and I'll give you the contact info on my source.
In terms of potential tank mates: I've found this to be the trickiest part of the whole process. My experience has proven that most other fish fall into two categories.
#1 Those which may/will bite, pick at, or sting the sharks.
#2 Lunch.
There are several which I have not yet tried, but all of the tangs, damsels, groupers, etc. etc. have been killed and eaten. Most just couldn't out run my black tip. Some could, and would hide, but the shark is very determined, once he'd made up his mind he would do whatever it took to get the fish. Jim27 was right about me being ready to give up. But, the sharks prey is not limited to what he can fit in his mouth or swallow. The shark recently explained this to me when I added a 8" Gerabaldi damsel. He has no problem making them "bite size."
