Hi, I just upgraded to a 20gal! In it right now is: 1 male betta 4 albino cory cats (soon to be 6) 1 mystery snail (soon to be 2) I was at first happy with how it is, everyone gets along very well! But, my boyfriend says he'd love some more color and I couldn't agree more! Its bare in the middle. I told him to pick out fish he likes and he sent me a few, I was wondering which ones would work and how many of them we could have. -Gourami (I know they're agressive but I've seen people do this sucessfully, Im wondering if its a good idea if I'm prepared to separate them?) -Discus -Cherry barb -Black molly -Black skirt tetra -Swordtails Thanks in advance!