Ive been through tons of fish phases, and planning on another once we move. I loved a set of shell dwelling cichlids I had, they were such interesting fish and started breeding within a few months, so I introduced a few friends to them. A set will do well in a small tank since they barely move away from their shells once established. Watching them clean out their areas and arrange things was fascinating. When I had multiples in a tank, they would carry sand in their mouths and dump into other fish's shells! The last tank I had going was a 90 gallon reef, all types of corals. Was honestly better than tv, could stare at it for hours. Once we get established in our next home, Im planning on a large freshwater with small schooling fish, live plants, shrimp etc.