I went to the zoo today and found out they've just finished building their 10,000g tank, it's got 10 cownose stingrays and 1 bamboo shark that I saw and they're getting another 50-100 different stingrays, its gonna be one of those pet the stingray tanks.
Not very exciting photos and stuff yet but here's a link to their web site
http://www.calgaryzoo.org/cownose_rays/index.htm
the tank is a big oval, looks like a race track and the rays just swim laps mostly just a nice smooth sandy bottom thats 2.5 feet deep in the center and tapers up to the edge where the kids can touch them.