So when I put my little Goby in the DT tank soon I'm concerned some of the crabs that hitchiked in might be a threat to him and even try to eat him possibly so I'd like to try to remove as many as I can in the next few days although I know I can't get em all...what are some techniques for removal. I've heard of the "bottle neck" technique but forgot how it works. Can someone refresh my memory and/or offer other effective removal techniques?