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new bimac troubles


Blue Ring
May 13, 2003
Hi all,

just joined and i'm finding this forum extremely helpful. :biggrin2:

here's my prob. just got a new bimac 4 days ago. he's in a 35gal which he shares w/ a serpent star & 1 black & white damsel w/ about 30lbs of live rock & a sandy substrate. sg 1.024, temp 77F, pH 8.25. when i first release him into the tank, he shot across the water and planted himself on a piece of rock. he sat there a min and pulsated colors, then ran inside a cave and i haven't seen him since. i've tried putting chopped fresh shrimp & scallops in the tank, but nothing has made him come back out.

last night, out of fear he could have died someplace in the rock, i lifted all of the rocks to look under them, but never found him. i suppose its possible he's inside a hole in one of the rocks and i simply didn't see him.

what should i do? any opinions? is there a recommended way to make him come out or at least find him? i don't want to disturb him all the time if he's simply scared, but i need to know if he's still alive!

Welcome to TONMO.com!

How small is he? Could he have possibly escaped the tank?

I'm not an octopus owner (there are many here), but from what I've read it's fairly common for octos to take a while to acclimate, some longer than others. Four days does seem to be a long time...
Hi there! Welcome to a great source for our ceph obsessions!

If I were you, I would leave him alone! He's probably found an excellent hiding spot and sooner or later curiousity gets the better of em and I know when I'm not sure where a new one I have is, he's usually in a spot where he can see me but I can't!!! Give him some time to get used to his new surroundings! Also, I bet he's out when you're not watching!!!!!!

he's about 1" (his head). i don't think he could have gotten out. i really took the words "escape proof" to heart when i built this tank. he'd have to be able to pancake down to the thickness of a sheet of paper to get out of this thing.

i'll leave him alone as you suggested, but how long before I should become concerned?

plus, now i'm worried that when i put the rocks back i could have trapped him somplace. although i assume he could dig his way out through the sand if he's really ok. there's about 1.5" below the rocks and they're not piled heavily.
also, a lighting question

i have the tank lit only by a single 15watt actinic blue flourescent tube. that keeps the tank fairly "night-like" i've had the lights on 24x7 since he went in there. a friend with an octo suggested it to get him used to me. could this be a bad idea?
one more question

another question, how do bimacs feel about freshwater ghost shrimp? i already stock a considerable amount of them for my african tank and it would be very convenient to use them here too.

(dunno if it will show up, but i changed my ID to stevesfish now so it matches my email)
I'll try to answer two of your questions:

I have a 30 watt fluro bulb and leave it on for about 8 hours to have an octopus "day". The actinic blue isn't quite what you need for an octopus, and leaving it on all the time gives your bimac no day/night. Maybe your bimac would come out more if you would switch out the bulb.

Also, I fed my bimac ghost shrimp until I could find other food he liked, and once in a while still offer a few ghost shrimp. Ollie has always liked ghost shrimp (and any sort of shrimp).

thanks nancy, all of my other tanks have a day and night. i guess i was trying to create an "always night" lair for bob (thats what i named him). i'll put it back onto a timer like my other tanks and see what happens. i just turned it off, its 11pm here so he'll get his first night.

here bob, here bob, here boy . . . :shock:
Good deal on changing the light to a regular schedule...that really bugs them when there is always light on! Probably the best thing you can do re: food, is to offer different items all of the time...hit a local baitshop and see what they have...lots of TONMO members are recording good luck with killifish,etc from baitshops. I usually buy my shrimp/ crawfish from there...
Hope he comes out soon!

First, welcome to TONMO!! :biggrin2: Please be sure to enter your tank in the OCTO Database if you haven't done so already.

My bimac, Tralfaz, took several weeks until he seemed to be comfortable moving about the tank on a regular basis. The most important thing is to be patient and allow him/her to feel secure. As difficult as it is, try not to move things around in thetank and offer food avery couple of days. I would leave the food in over night (he/she may feel more secure eating it then) you can remove the uneaten food in the morning.

I'm not sure about actinic lighting, but you should definitely have a timer on the lights.

One other thing, GET RID OF THE DAMSEL :x Damsels are notorious for being bullies. While your octo would likely eat it when he/she got big enough, the damsel will attack and stress out the bimac all the time. Hope this is of some help.

I know this is going to sound horrible, but I have had to do this in museum tanks before...get a very small trout hook, and bait it, and catch the damsel. Ok, ok...I know...cruel, cruel...but it works.
tonight i think i may have my first evidence that bob (my missing bimac) is in fact alive! :bugout:

that troublesome damsel we've been discussing is missing. i'll have to wait for the lights in the morning to make sure he's not hiding someplace, but if he is truly gone, i'd have to say it was bob. the only other thing in the tank is a serpent star and he would never catch a healthy damsel without help.

i'll let you know.

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