The beautiful L-144's (I know, controversy. but for our purposes they still remain L-144s to me) ......long flowing fins of course. :grinyes: They stay about 3-4 inches.
L104, L260, L046, L340, L400. Those are the ones I keep in a 20L. Each has their own tank. LDA08 would be nice, too. You could keep a few of those. Good luck.