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Reclusive Bimac


Dec 6, 2002
Two weeks ago I traded my strictly nocturnal species of octopus for a bimac from my local LFS. I'm not sure of the species I had, but he was primarily red in color and never seemed to change much compared to a previously-owned bimac. He was very active during the night and ate freeze-dried shrimp everyday, but as soon as I turned on even the dimmest of lights he disappeared into the sandbed. It was very hard to "trade" him in because he was doing so well, but I could never seem him except under a red light and even then could never really see him. So reluctantly I swapped him for a bimac that my dealer had ordered for me. When the bimac came in, I let them keep him for a week to make sure he was healthy and eating. When I went in, he was out and interacting with the customers; so I decided to make the trade.

After I put him in my 75-gal tank he seemed to adjust quickly. He was out and about later that evening and was coming out in spurts for the next few days. He ate some ghost shrimp I put in and I think one hermit crab. However, for the past week he has stayed in his lair (a fake barnacle) and covers up the hole with an assortment of small rocks and empty hermit crab shells. A couple of times I have removed some of his "wall", but he quickly sticks out a few tentacles and covers the hole back up.

I had the water checked and the water quality was excellent. The SG level is 1.025 and the temp is approx 76F. The only other inhabitants in the tank are two starfishes, an urchin, two snails, two conchs, a cucumber and three hermit crabs (inteneded as food).

I guess I am asking am I losing this one? My previous bimac was much more active than this one. I might also add that I had my nocturnal guy for over 2 months under the same water conditions, if that helps.
I dunno...I'm told bimacs can vary in behavior...but he WAS social earlier, you say? Hm.

I was in the same boat as you when I got Gollum...a very small and incredibly timid octo whom I have NEVER seen "out and about." Whenever I catch him, it's always in a den or trying to pretend he's a rock up against the glass! :P I was very worried early on because he spent almost two weeks in the SAME SPOT up against the glass, which he had run to right after introduction. Since then, I've determined that he really did go out exploring the tank...it was just that he was treating this spot as his den for a while before he became comfortable enough with his tank. He's quite healthy, so this behavior seems to just be part of his personality (and species, perhaps.)

Could be that your bimac just hasn't quite become familiar enough with your tank yet, so he's found a safe spot and is sticking to it for a while?

Hi again,

well i think that if you just fed it when it was out and about hunting that you would se it more. Chances ar eits full and doesnt need to come out... I always feed my octopuses at the time i see them hunting, especially with the bimac, it seemed to be seen so much more if i only fed it what it needed, then it would hide for a day and then back out hunting the following..... just an idea, i think that there is nothing wrong, just a well fed ceph :smile:

what size is the bimac?
His mantle is about 2 inches long and he only has four tentacles and they are at least 6 inches long. The remaiining four are missing all the way to his body, but when I last saw him; they were starting to show new growth. I just returned from having the water checked and the nitrate level was about 5 ppm. I also added 5 ghost shrimp a few minutes ago. I can definitely see movement from him, but only so much as to stick an occasional tentacle out and rearrange the shells inside his lair. Not sure if he will eat any of them before they succumb to the salt water.

Your nitrate level is no problem to an octopus so no worries there...

Use some 'tough love' here :smile: Dont feed the octo until it comes out looking for food. That way I guarantee you will see it way more than you are just now. If its busy making a den just leave it, thats good behaviour to see, let it do that and it will feel more secure and when it gets hungry it will crawl out and go looking for food. They are diurnal so you should see it during the day.

On average Id say i give octos about a month to settle in before i decide whether its going to be a recluse or not. Im sure that yours will be just fine... Let it work for its food... 5 ghost shrimp would last an octopus that size a good few days.

All the best
Thanks for the advice. He actually came out some last night with the lights on and checked out the rest of the tank for a few minutes. He constantly stuck his tentacles in every hole in all the rocks like he was looking for food and I'm sure he found a few of the ghost shrimp. I'll give him a few days before I try and feed him again as you suggested. I also turned the heater down a little to get the water temp down to hopefully 74 (it was closer to 78 before). I'll keep you posted on his progress.

Dools :smile:
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