First time octopus keeper (for less than a week). I have been reading other threads that have mentioned heavy breathing as a warning sign something is wrong. At what point is the breathing considered "heavy"? I can see his siphon open and close and his mantle slightly rise and lower, but I'm not sure what the standard is for heavy or normal breathing. Are there other warning signs I should keep an eye out for along with his breathing? He does have dens (he has made several) and does eat at least one large, live shrimp a night. Thank you for your help!