When the kids were small, we went to a wedding that had glass vases with bettas swimming around, tap water change weekly and that fella was around for quite awhile. I might just do that with an Ivy or something on topOne of my favorite tanks was nothing but fancy goldfish and gravel. Small tank, no filter, just weekly water changes for years. Wife bought me another goldfish and lost everything soon after due to some goldfish disease. Still...very simple, very easy, and just loved watching it. That's part of why I want the shell dweller tank.
But no plans to give up the Reef. I'm enjoying that far too much.
Ever have a Newt, their are some colorful ones and would be perfect.My wife has given me the go to dismantle "her" FW cube tank and turn it into a terrarium...it may not have the space for fish, but may try some amphipods and snails.