Please don't take offense but personally I think a colum aquarium is probably one of the worst aquariums for any fish. Fish like to swim side to side a lot more than they do up and down. A column aquarium really doesn't give a fish a lot of room to move especially when you realize that certain types fish prefer certain areas of the aquarium, i.e. top and bottom dwellers.
Then one must consider gas exchange. It's better to have as large a surface area of water as possible. A larger surface helps with the mixture of oxygen and water and also serves to releas Nitrogen and Nitrous Oxide which are byproducs of biological filtration.
A standard XXGal tank will hold more fish than a column XXGal tank. With a smaller surface area for gas exchange a column tank can't handle the same bio load as a regular similiarly sized tank. Adding an air pump and airstone will make pretty bubbles but won't compensate for the decresed surface area.
Bottom line...column tanks short change the fish. If you look at conventional rectangular tanks you will notice that they are wider than they are taller. The newer corner, hex and column tanks that may be more visually appealing to humans certainely weren't designed with the fish in mind. Personally, the only fish I like to seem in coumn tanks are plastic fish.
Respectfully,
Gary
