Water flow simulator?

[bigmac]

Ok; based on the non-responses; I'll assume that I'm out to lunch and this doesn't exist.
What a fantastic tool that would be though:
1. Input your internal tank dimensions (water height,etc.)
2. Input your bulkhead locations.
3. Input the gallons per hour and return line size for all the pumps (including head height).

With all that information you would get a simulation of water movement within the tank (and more importantly be able to tweak your setup or equipment before the drilling of any glass). What it wouldn't be able to take into account is live rock and the affect it has on water movement.

Oh well; I'll consult my tank builder when it's time and he'll let me know if my plumbing plan will work.