I have a Aqua-medic T1000 Blue which I find does a very good job for the price. You can get it from
www.aquacave.com (they ship to Canada) for only $179 and our CAD dollar is strong right now. It's 18" high according to their site, but I have never measured mine. I have a 70G mixed reef and I get a full cup of ugly skim-mate every week like clockwork. It can be used as an HOB or In-sump (which is what I do)
As you can see, the bubbles are quite fine and it's easy to set and forget.
Hope that helps.