hi, i have one of them right now(male) and it's perfectly happy- but you gotta keep
the water about 73-87 degrees since it's a tropical species. and if it's full grown,
pay close attention to its first pair of walking legs- if they're normal, it's a female, and if it's kind of plump(maybe even fat) it's a male. and if it's happy, it should start to turn reddish, starting from the center of fans, end of its 'feelers' and/or develop whitish line down its back(starting from the tip of the mouth). most shrimp live about 1-2 years, but this one lives up to 5 years. DON'T put it with cichlids, even small ones.
observe closely, and if any of the fish is bothering it, put it in a separate tank. oh, also, it might seem like it's living contently for a few weeks with a colony of fish, but in most cases, it might be STARVING TO DEATH. in my case, i've got algae eater and 3 goldfish- and they're living in harmony.
the first time mr.shrimpy molted, i thought he turned transparent, although it's a stupid conclusion. i've discovered, in some cases, Mr.shrimpy eats the fish's POOP. ha.. ha...
p.s. if the tank is too big, it might be hard to find the shrimp.