Bottom Times out of Brockville (with Evan and Anick) get my thumbs up any time. They are who I use anytime I want to dive that area. Trying out a charter company in Kingston that they recommended at the end of the month - should be great. A few of us are meeting in Kingston to do a 2-tank day. Boy am I counting the days (I only have an OW class to DM from now 'til then, so I'm itching to get wet) The wrecks are up for discussion. Any suggestions?
As was said by Ontario Diver, each of the Great Lakes is a bit different. The only similarity that they have is that they're all fresh water. They all have thermoclines to deal with, but with the cold deep water most of the wrecks are reasonably well preserved. Then we have the "famous" brown fish, green fish and don't forget the elusive brown & green fish (lolol). Well they do look like that, though I have friends who have taken powerful lights with them and they claim that the fish have more colour.
Enjoy, if you head up my neck of the woods St Lawrence / Lake Ontario, drop a line, perhaps we could get some of the other Neptune Divers together for a dive (or two or ...)