So, I guess Grendel has been with you for about two weeks now? It is possible that there are times that Grendel is watching you but you don't realize it - maybe very well camouflaged or just under a rock? I did see this kind of behavior for a bit from the first aculeatus but it didn't last long. Something else just occurred to me. Another possible difference is that the tank I had them in is in my studio where I am 14-16 hours of the day. It may have been that they were extremely familiar with seeing me there - lights on or off on the tank. Speaking of lights, do you use a night light on the tank? Are you able to spend much time around your tank? If not, and you have the spare time, you may try just being in the room going about your business as much as possible. I realize that may not be realistic for you. The tank may not be in a room that it is convenient nor may you have a lot of free time outside or work. I'm only able to pull off this stunt because I'm literally trapped at home (due to illness) and work/goof around in my home studio now. My octos keep me company...
If you are using a nightlight you might want to try turning it off. After I tried using one for a few days dwhatley suggested not doing so and it helped Goo calm right back down.
I actually sleep and have my computer in the same room with the tank, so I spent lots of time in there. It is very possible he watches me without my knowledge.

The tank does have some very dim blue "moon" lights, I can turn those off and see if helps.
Yeah, you probably should turn off the nightlights for awhile. For some reason, I think it tends to make them a little restless. Can't hurt to try right?
I just realized I never uploaded the pictures from acclimation.


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Finally trying to coax him out of the bag and into the tank, he didn't want to go.


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Some pictures I took today that demonstrate his camo, which is MUCH more effective than I gave him credit for. He is not in the third picture... I don't think I could spot him without the picture where he's gone. Still got some fuzzyness issues with the camera (and the flash makes everything an ugly color, urg).


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Wow very well hidden , I think I spotted him. It really does not look like a briarius they don't really show good camo like this. Grendel looks like an aculeatus to me.
Thanks Dean that is the same conclusion I had come to.

He's eaten all of the hermit crabs in the tank now, seems to ignore the snails and serpent stars as if they dont exist (the serpents actually crawl into his den with him to try to steal bits of food.)

He's less shy now but only by a little. He still doesn't go far from his den when I'm in the room, but he will poke his eyes over a rock and watch me. I can also coax him out with a fiddler crab, but not for longer than it takes him to grab it and take it back into the den. He wont take them from my hand, but a few seconds after I drop the crab onto a rock he is all over it like a fat kid on a cupcake. He's extremely quick when he wants to be, but most of the time he slinks around. May as well throw up a picture of his eyes, since that's all he will let me see with the camera (I'll try to take video of a fiddler crab attack tomorrow.)


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Pretty much the same. Still very antisocial, will only come out with me in the room if I throw food down near her den but she leaves plenty of evidence that she roams around the tank when I'm not there. A couple mornings I've caught her sleeping stuck to the front glass, which I thought was odd, when she woke up she sprayed ink and jetted back into her den.

I'm wondering if there is something I can do to help her realize I'm not a threat. She wont eat the frozen shrimp I purchased; she acts like it's not even food (used a piece to block the entrance to her den, for example.)

I am fairly sure it is female now, having caught her sleeping outside the den I was able to inspect for a curved arm or larger suckers and there was none.
Wow that is odd she was sleeping out side of her den.:lol:

At first my octo wouldnt take frozen shrimp, but when we got in a rousing game of tug a war i would slip a shrimp in my hand and he would take it. Also if he reach is reach out to grab it start pulling it and stuff to see if it interests her that it might be alive. That worked for my octo.
So I'm thinking now that she's not going to be around much longer, since last tuesday (6 days ago) I have not seen her leave her den. She completely covered the entrance with shells, if I moved them she'd reach out to put it back. Hasn't eaten anything, yesterday I noticed the sand been blown up to nearly completely cover the entrance so I can no longer see in to see if she is alive.

I'm curious how long I should go without a sighting before I move pieces of live rock (I would need to heavily disturb to the tank, given where she decided to stay) to see if she's even still alive.
Best guess (from some of the prior posts) is about 10 day brood time. She may or may not exit the den (Serendipity did not, Beldar and Trapper did) at the end of that time.
An update for posterity, at 14 days since she began brooding behavior she is still alive and still not leaving her den or eating. Unfortunately I cannot see her at all in the den to check, so I've spooked her several times by moving a rock, the eggs have not changed in size or appearance since I first saw them so I believe they are not fertilized.

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