Dwarf puffers ftw! I have 6 (my gf's but guess who takes care of it) in a pretty thickly planted 10g for over a year now with no issues. Just low light plants and marimo balls. Also have it stocked with cherry shrimp. Puffers leave them alone. Lots of personality, cute, fun to watch shrimp and with stocking mts and tossing blackworms in every so often they tank self feeds quite a while.