I got the octo this am and he looked alright so I put the bag in the tank to start acclimating. I would check on him every little while and after about an hour I looked and he started inking so I manually took him out of the bag, having to get the suckers loose, and just held him in my hand in the tank. He was sticking to me but not moving, BUT he was breathing. I held him in the tank for 30-45 minutes and now I have him in a glass bowl with an air stone. He still has not moved his arms but he is still breathing and sometimes the breathing gets quite aggressive. I don't know, can octopus have strokes? I am a medical person. Is he dead or alive? What should I do?
At least your octo had some acclimation. He may be suffering from stress or fear. It's really hard to know what the right thing to do is, but are the water parameters in the tank the same as in the bowl? I'd consider putting him in the tank where he would have a more natural environment and feel more secure. He could hide, rather than being so exposed.
I don't know whether an octopus can have a stroke or heart, but some of us have observed something similar as an octopus is passing away.
I have noticed O. briareus seems to be especially prone to being stressed and not moving for an extended period of time during normal acclimation. Hopefully, it has moved by now but if not, I would turn off the lights and leave the room for awhile.