Mine is real peaceful, but it did grow fast. They shed (molt) and that is one of the reasons I use combi-san in my tank. Its a tad spendy but lasts a long time. about a drop per gal once a week. I'm still on my first bottle. It will help it to strengthen it's shell when it does molt. Don't freak out either . One day you'll think the shrimp is either dead or multiplied. Look close they even shed the antenea. I wouldn't put more then two in if they are small but my one takes up "his own space"