So interesting story, my wife's favorite fishis a Diamond Goby and so we MUST always have a diamond goby in the tank. Well we lost our first one to an unfortunate carpet surfing accident. So off to the LFS we go to acquire another one. Acclimated it and placed it in our tank only to "never" see it again. Two weeks later my wife and I give up hope that it had made it and thought we had lost it. Or sandbed was also in dire need of a hard working goby. So off to the LFS yet again to replace a 2nd diamond goby..... Well low and behold three days after introducing the 3rd goby into the tank we finally see the 2nd goby in the tank. The 2nd goby had burrowed himself for at least 3 weeks and now is out and about working hard. My question is will the coexist?? I have a 240DT. They have their burrows on opposite ends of the tank for now, just wondering how long this will last or if i should expect to see some jarring at each other at some point?