a mantis shrimp would be cool, the way i see it, when i first started off with FW i didnt have a tank with one fish in it, i had a community tank, thats what interested me, then as the hobby grew i found more things that i wanted and 1 tank turned into 10 tanks, started getting more rare and or more carnivourus, so considering this is my first SW and ive dumped alot of money on it, i would enjoy a more full peaceful tank with lots of fish as apposed to one guy in the tank, probably down the road i will start a tank for a mantis shrimp, so its not that i dont want one, i would just rather have a community tank