Jack and Jill (my jack dempsey's) are gonna love you. But judging by the size of the crab, they wont like eachother very much, cause only one of 'em is gona getto enjoy a crab of that size..
Just to let you guys know after about 2 months, i found the flippen ID. http/www.wetwebmedia.com/swcrabfaqs3.htm
third crab down. I'm planning a mantis for this tank, and the crab will be around the welcome him.