Are Krebs a burrowing cray? The reason I ask is that I sometimes only see one, two and up to four in the tank. They are very small yet, so I think the ten gallon will be OK for a little while longer ...... since I put them into the tank, I haven't been able to find all six at one time yet, but I counted six before I put them into the tank! I've been using ground goldfish disks, frozen shrimp, and freeze-dried tubifex worms for food, they seem to be keeping it cleaned up (no complaints to the chef so far) ...... I understand that they will eat each other IF one is moulting, so I'm hopefully going to end up with 3 or 4 adults at least :crosses fingers, toes, eyes: