They have all come from the same section of the Halswell river around 10km upstream from where the river meets lake Ellesmere. The last darker colored bully has an orange band on its dorsal which makes think it is an upland bully.
thanks for the help, i have only just got interested in natives and love exploring the streams around my area. I have a bunch of tiny clams in the tank also, the other night the Koura stepped into one and it clamped down on its hind leg and he was dragging it around for hours, gave me a good laugh.