I thought dither fish are used mostly with small SA dwarfs, like apistos and rams. In that case, balas and tinfoil barbs are a bad idea. The dither are used to make them less shy by creating a false sense of security - dumb fish swim out in open, they get eaten first while we have a chance to hide. Also, it helps create the sense of a breeding territory to help form pair bonds and start harem spawning. With the dwarfs, you want smaller, quicker, and not nervous fish. Harlequin rasboras, Cardinal tetras, neon tetras, pencilfish and kilifish are all fairly good choices. Danios, large tetras, and pretty much anything bigger than your dwarfs are a bad idea. It also helps to divert the male's killing tendencies towards something else and not your prized female.