...need some space to walk between tank and couch.ughh
the general rule of thump is go as big as you can afford. Meaning the bigger the tank it will cost more on equipment, stocking and running it.
I started out with a 30 and upgrading to a 90 2 month later. I am in the process of going with a 120 cause of the 24" width. Hope this helps and my .002 cents worth.
What did you end up with?