Bumble bee gobies are a unique bottom fish. I personally have a 10 with a dwarf puffer and a few bumblebee gobies. both are great fish. I also have a couple amano shrimp in there and everybody gets along great. You can also look into Celestial Pearl Danios. They can be hard to come by and a little pricy but only grows an inch max and look absolutely stunning with plants. I personally have a small school in a 12 long and they're def a conversation piece.