I have a question about danios and cories. Will either of these fish school with other species of danios or cories? I read on one website that cories will only school with cories of the same species. Is this true? As far as danios, I was wondering because I have one green barred danio and would like to add fish for it to school with. I originally bought 5, and they were doing fine until I bought a catfish from the same store and it and the five danios all got ich. It was strange because only those six fish I got from that particular store were affected. Anyway, four of the danios died, so now I only have one and haven't been able to find any more like it. I have four pearl danios in the tank with it and they don't seem to pay any attention to each other, so I assume that if danios do school they have to be with fish of similar size. Would another large danio species, such as the giant danio, school with the green barred, and would another smaller species, such as the zebra danio, go with the pearls?