I just got a Tiger pistol shrimp and yellow watchman goby 2 days ago and they haven't paired up yet, but i'm hoping they do. I bought mine on Aquacon.com and i'm not a fan of them just as a heads up. They call you before they ship your order which they did but never ship me 3 other items I ordered for a friend and never told me until I called and complained. Plus a lettuce Nudibranch died as well, and they won't reship everything until I buy something else which means I'd have to pay another $50 for shipping which is crazy!! I suggest you go on Saltwaterfish.com and buy a Yellow watchman goby and Pistol shrimp paired up already. They were like $30 which isn't a bad price.