For CA/SA, I can't recommend anything in the Chicago area, and other than Chicago Aquarium, I've visited all of the aforementioned LFS many times. Selection for new worlds in this area is limited and the quality is usually below average. For CA/SA, I strongly recommend traveling an hour north to Milwaukee to Hoffers Tropic Life Pets and Aquatics Unlimited. If you have the ability to go west for a half-day, Roe's Aquarium in Rock Island, IL has a great selection of quality of CA/SA - the oscars in my avatar were purchased from Roe's. I second the recommendation of GCCA as another source - including the swap and auction events, the club does coordinate group buys from suppliers.