Both of my 6 month olds (O.briareus) den at the back of the tank and have removed the sand in favor of the glass. Here are two videos of KaySoh (videos 3 and 4 on the post) shoveling the sand away from one place and putting it in another.
So far I have found shell on shrimp is the easiest to be accepted as first dead food. Monty will only take food with shells (this is a first though). No matter what we offer he will take it if it has a shell and totally refuse it if it does not. I recommend using a feeding stick over trying to hand feed. Be aware that it is almost guaranteed it will try to capture the stick once it is accustomed to finding food at one end. Some people will play tug of war and others just wait until they are tired of holding it. If you play tug of war, note that it is likely to pull hard enough to dislodge the live rock (this goes for hands too).
Thanks for the advice, I have some frozen shelled shrimp as well so I'll go ahead and defrost one and give it a go. It may also be that he's just plain not hungry (I assume) as there are plenty of crabs for him to snack on.
Let's hope he is just not hungry because he ate a crab and that she is not about to brood. I am never comfortable with a new octo until it has been in a tank for 2 weeks. If they make it into the third week then chances become pretty good that they will acclimate and live through until senescence (or until eggs hatch or would have hatched it they are not fertile). I have not had a crab survive more than 48 hours but if you have multiples, he may continue to hunt them until they are gone so watch for crab carcasses.
Definitely, will do. There are still many crabs in there so it's a distinct possibility. Is there any particular behavior you can think of to watch for that would point toward brooding? (other than the previously mentioned reason)
At this point, other than seeing eggs, no, not until the octo is settled (roughtly 3 weeks to a month).
For an octopus that has been fully tank acclimated, a major increase in appetite and activity is always forboding, collecting den doors (any loose shells or small pieces of coral) and building a forterss is typical (and sometimes changing fortresses and bringing the collection along) and finally, refusal to eat or leave the den. My brooding larger octos (not O. mercatoris) have all chosen to make their brood dens where there is good water flow, so they pick dens that get constant movement from the Koralias.
Still didn't accept food tonight though he did pull it into his little hiding space for a bit and then push it out (shrimp). I then tried a scallop for good measure and it was just a touch and release. I did come home to the dark room the aquarium is in with only the night leds going and he was out and about. As soon as he spotted me walking toward the tank he flashed red and moved behind a rock keeping only one eye on me. I just sat in front of the aquarium for a bit and he eventually lightened and just sat staring at me. The local sleven has freshly refrigerated ghost shrimp (and i have absolutely no idea why by the way), what do you think the chances he'll take one of those are?
All that being said, a snack of freshwater shrimp won't hurt (very weird thing to find at a seven eleven though and I would inquire about why they have them there. I could see bait shrimp if you are near a lake but ghost shrimp is peculiar).
The newest thing I found (and have been meaning to post) is the snails sold at my international (primarily Korean) food market. I don't know the name but they are saltwater snails and all three of my octos eat them where they rarely touch other snails. I also tried squid and cuttlefish without luck and minimal luck with abalone.