I've had a pair of maroon clowns for over 2 years. Big momma is about 3 inches and Little man is about 1.5 inches. They are my fish sidekicks. They've been in 4 different tanks and even survived a 3 day car ride when I moved from California to Colorado. They've lived with jawfish, pipefish, cardinals, blennies, and gobies and a six line wrasse. The wrasse was the only one they didn't get along with. I finally rewarded their years of service with an anemone tank all their own (except for a yashia goby who lives in a cave at the bottom of the tank). I guess it really comes down to how they are introduced. If they are in a tank by themselves with an anemone and a new "swimmy" fish (not a rock/bottom dweller) is introduced, they can get a bit ****y. Basically, they are territorial and once they stake out their "zone" they don't like other "swimmers" entering it.