I have noticed a change in Kang, and I am not sure of the cause. I hoping its not senescence, but I can be realistic that it might be. About a week ago, I needed a rock for another one of the tanks I have. I pulled a small grapefruit sized rock out of Kang's tank. I was not part of his cave by nearby, maybe 8" away. Since then hes gathered all the shells and rocks he can find and barracaded himself in and hasnt been himself since. I'm hoping its coincidence. He ate this last weekend, but nothing since. I usually feed him 2 crayfish every other day or so, with maybe some small frozen prawn/krill in between. Additionally he was very active always crusing around the tank morning, noon and night. He has ceased this activity. I stuck my hand in yesterday and pulled away a rock covering his cave. He flung a few arms at me, but didnt come after the rock. Eventually he came out fully, in a mottled color white/brown like he does when hes alarmed. He wrapped a few tentacles around my fingers, but quickly lost interest and went back to his cave. I next tried the sure fire method to get him out. In the past when I put in fish flakes and/or Formula one, he'd go bonkers, and come out like he was on fire. Not so yesterday. He doesnt appear to have any sores, or un-naturally pale. Though, occasionally he does appear in his cave as white with black around his eyes, but will go back to his normal coloring. I have not seen any eggs, but that does not mean they arent somewhere in the cave that I cant see. I have not been able to interact with him the last couple of weeks as much as usual too, and since he disassembled the powerhead again, that hasnt been up and running for a couple of weeks as well, so he lost a toy. My question...is this senescence, or could this simply a reaction to the rock being gone and less interaction from me and the powerhead. I know they thrive when their brain is exercised, could this be a combined reaction of the above, or is it possible that Kang's run is coming to an end. He is fairly large, but I do not know when he was born. I should be getting more crayfish today (ran out tuesday), and will try feeding again to see. Any insight would be helpful as always. I would hope it wasnt senescence, since Ive only had Kang since January, but it seems it may be a possibility.