I just set up a fish only that 20 gal.long with 40 lbs of LS and 20 lbs of LR. 2 rio powerheads and a sea clone PS. would this set up work out for a lion? it would break my heart to put one in and have it unhappy.
I wouldn't do a lion, of any species, in a 20gal tank. IMO, dwarfs need a 35gal minimum to be comfortable. Lions, being aggressive fish, will still disrupt the water quality of the tank (although not as badly as other aggressive species.) You really can't do any aggressives in a 20gal, they just need more space. Bo