I want to get some bumblebee goby but not sure if to add them together with the killifish. My water are pretty hard (PH 7.6+ high GH & KH) and they seem to do great. I've read in seriously fish that they found sometime in slightly brackish . I need to shoot for low end salinity 1.003-1.005 for the goby. I'm not sure how could this effect the killi so I thought I better ask more experienced.