It's not really aggressive, so to speak. It will move if it wants a new location. They don't go around like "hmmm, what corals and things can I kill today?"
Their tentacles wave with the flow, so if a current is so inclined as to blow the condy's tentacles right onto that nice new coral you got, that's what'll happen. From what I can find, it's a very powerful sting. One reference (at liveaquaria.com) says Red-Legged hermits will eat it. Don't know how true that is, but I figured I'd throw it out there.
Temptation is a killer. I haven't even gotten my liverock and I'm goin' all crazy. I'm no condy expert, but I'd definitely say 2 is a max in a 29, and I'm not even sure about that. But I know, and have to remind myself constantly, patience and planning is the key to a successful sw
tank. I saw little tiny carpet anemones in my lfs
, I'd say maybe 6" in diameter, perhaps slightly more. They were too cool, but I still know I'm months off 'til I can get those. If I even want a carpet. I'm thinking bubble-tip. But anyways
125 gallon saltwater: 55gal sump, 4 Blue-Green Chromis, Purple Tang, True Perc, Firefish, Royal Gramma, 5 Ricordea, Bubble Coral, 15 Pulsing Xenia, Green Star Polyps, Deresa clam, Green-Tip Torch Coral (about 11 "heads"!), Orange Montipora Cap, Purple M. Digitata, Green Slimer Acro. Yongei, 3 Orange M. Digitata, Pink&Green Acro. Millepora