The Durham Aquarium Society is holding their annual all day event called Aquariama 2012 on Sunday April 15th in Ajax, Ontario. Here is their link. Durham Region Aquarium Society - The Front Page
This is an auction event. You can sell items you have or come sit, watch and bid... hopefully successfully on the new fish friend you want.
I attended last year. I saw a 2nd hand area where you can sell your items (old tanks, pumps, filters etc), a judging area on certain categories of fish species. Also tables and tables and tables of numbered and labeled bags of fish. Peruse the tables, find something you like, record the number, then sit and wait for it to be called and bid! Please see the link for all details required or contact them for requirements and payment details. Likely cash is best.
I really enjoyed myself last year and will be attending again this year!
You do not have to be a DAS member. It was held in the south end of the Sports Complex with it's own entrance off the south wall. Not the main entrance.