Paradise fish would be different, but then again I usually recommend those :red_mouth - they are my favorite fish! Anyhow, a tank that size could easily hold 2 males and 6 females, probably more if it's longer than 4 feet (male PF's need 2ft each to build territories). In groups, the PF's would be far less likely to harass their tankmates than lone fish or pairs would, especially if the water disturbance is too great for the fish to build a bubble nest (expect trouble if they manage to breed).