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[Old Board Archive] New octo timid or stressed?


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May 30, 2000
New octo timid or stressed?|rrtanton|
Well, with much research and advice from wonderful TONMO members (and a deep breath) I've taken that last step...my first octo arrived Friday morning. With some discussion, I settled on a "pygmy" octopus (possibly O. mercatoris.) He's quite small, probably a bit smaller than a shooter marble if you ball him up, so I'm assuming he's pretty young.

I have some nervousness about his behavior and lack of feeding. Upon arrival, he was quite active in his bag, though he hid in a corner of it once I started acclimation. Once I was done acclimating, I gently cut the bag open, and with very minor prodding he rather enthusiastically jetted out into the tank. After about a minute, he made a beeline to a corner of the tank near my intake tube--and has been hiding behind it ever since. He did move downward a bit after an urchin came close. In one shape or form, he has been there now for the past 60 or so hours, and has made no attempt to feed.

He certainly seemed capable of vigorous activity, and I haven't seen any obvious (to a newbie as myself) signs of illness. He is mostly white, though occasionally flashes patterns. I suspect he feels somewhat threatened by me, and by my few attempts at feeding him, such as gently dancing pieces of shrimp and scallop in front of him on a skewer, plus a ghost shrimp that luckily swam right up to him. He even lashed out at a piece of scallop with a couple of arms but it seemed more of a "get out of here!" kind of gesture. I backed off at this point, afraid I was just terrifying him.

I DID leave a piece of scallop and shrimp nearby his "den", and at some point they vanished...but I can't be sure if he was the culprit (one of the starfish might have nabbed it? ???)

He has shifted his position within his makeshift "den", but behind a tube against some glass seems an odd spot--there's tons of live rock riddled with crevices in there. As far as I can tell, he hasn't explored at ALL.

Sooo...is this a not-abnormal settling-in period, or is he mortally stressed? Or something else?

Water details:
Nitrate, Nitrite, Ammonia: approx. zero
Salinity: 1.026
pH: 8.2
Temp: 76-78
Lighting: 8 hours per day, moderately bright.

Should be no threatening critters...no fish, just a couple M. globulus urchins, couple brittle stars (no greens!), a sand-sifting star, tiny blue-leg hermits...really nothing threatning I can think of.

So, to sum up, 60 hours after introduction, my small pygmy octo apparently has just hidden in an odd spot and has not explored or fed. Um...help, I think?


Re: New octo timid or stressed?|octomonkey|
Hi Rusty

Glad to see you eventually got an octopus!

Anyway, your octopus does seem to be a bit disturbed by the move... can you tell me what you have in the tank? EG rocks? how many? pipes etc etc.... I think that you may be needing to leave the tank in darkness, maybe even stick cardboard to 3 sides if it can see all the way round. If they can see all sorts of movement outside the tank it can freak them a little... so maybe best to try and give him soem time and space and PLENTY of hiding places!

I think you should quickly try and find a LFS who sells crabs of some sort, fiddlers maybe, octopuses really cant resist them! Better than scallops and ghost shrimp.

I still have several shrimps swimming about in my bimac tank, it has never even tried to catch one! That has been about 2 months now too!

keep us posted :smile:

Re: New octo timid or stressed?|rrtanton|
Hmmm. I could try this "blackout tank" method, maybe he would settle down after that?

The tank currently has:
~55 lbs healthy porous live rock, stacked, plus macrophytic algae and some fibrous, not-so-annoying hair algae.
~1.5-2 inches aragonite sand
Mechanicals...there's a powerhead at either end of the tank near the top, a CPR bak-pak preskimmer box, outlet tube and a grounding probe in the middle of the back, and at one end an Eheim intake tube (sucking water in at the bottom just above the sand) and the Eheim outlet "rail" runs along the back top on that side.
Complete Animal inventory (55gal tank):
2 M. globulus urchins (blue tuxedo)
1 small pencil urchin
3 brittle stars
1 Fromia sp. star
1 "sand sifting" star
6 Astrea snails
6 blue-leg hermits
1 elegance coral
1 pagoda coral
1 green star polyp coral
1 lettuce slug (originally intended as a pre-octo practice mollusc) that may have been accidentally lost when I plucked out some of the macrophytic algae a week ago.

Really, he didn't even have a chance to see any of this at all, or encounter any of it. He went straight to the nearest glass side when released, moved his position slightly when one of the blue tux urchins got close, and hasn't left since.

Feeding-wise...to get him out of this funk, I'd be willing to drop some money on my LFSs pricey crabs, but I'm afraid even the smallest ones they have may be too big for him. I think the smallest of theirs I've seen are some emerald crabs at about $8 and they seem almost as big as him. I do have blue-leg hermit crabs that would be a smaller size, but I doubt he's even seen them. Is it worth getting more of those and placing one near him? Should I consider dumping in a number of ghost shrimp? They're freshwater, so I'm afraid that'd be like dumping a bunch of meat in to rot... I haven't tried feeder fish yet, but it sure seems to me he's behaving fearfully and so I'd think a fish might just frighten him that much more!

If it would be any help, I think I can make a digital version of a photo of my tank? I dunno how to post photos, but I'm sure I could email it.


Re: New octo timid or stressed?|octomonkey|
Ideal! Try to email it to [email protected] and I'll have a look see. (if you can make sure the pic isnt too big with the kb :smile: )

I think you have enough rocks etc so i cant figure why teh octo would not have moved from its original point to the rocks???? ???

What is your lighting schedule and does the octopus have a time of complete darkness? I have found pygmies to be mostly nocturnal. One specimen i didnt see eat for weeks. Eventually it was seen to be feeding on amphipods that it was finding in the live rock... I tried this octopus (O. cf bocki) on squid, snails, hermits and just about everything else i could think of. And it still never ate like a bimac or vulgaris does... Do you have a sea food shop near you?? Maybe they will have a cheaper source of crabs or similar? What about crayfish? Bait shops sell them.... When it did eventually eat crabs they were only about 1cm wide, anything bigger got ignored. And at that time the octo's mantle was about 2cm or so long... HArd to tell as the octo was so shy....

you will be right not to chuck in a load of ghost shrimp. Unless you kill the shrimp and drop it right next to the octo, so it can have at least something to eat. But remove it if isnt eaten. Maybe try dropping the food in last thing at night before lights out and leaving it overnight? I have tied shrimp etc to nylon thread before so they are easier to pull out next day if uneaten.

hope this helps....

Re: New octo timid or stressed?|rrtanton|
Photos sent to Colin...anyone else interested in seeing 'em can ask, and I will email. I do have a couple very blurry octo photos.

Lighting schedule...well, there's two banks of lights, left side and right side, and they come and go off on in a staggered pattern, but the net effect is about 8 hours of light per day. They come on at about 6pm and go off at about 2am. I'm just using basic timers, no fancy controllers. I sat and watched when the lights came on once, and he didn't startle or show any obvious response at all. With the lights as they are, it goes to complete darkness when they go off at 2am, but during the day sufficient light bleeds through the blinds that he'd probably be seeing as if by a full moon. I was present the whole first day, but since then I follow a pretty standard 9-5 schedule, so he does have some reasonable motion-free periods. I will try shutting the lights off and curtaining the glass, should be easy enough.

I will check my LFS, but I'm not optimistic. I think the smallest crustaceans they have are the freshwater ghost shrimp and the blue-leg hermits. He had a ghost shrimp in an ideal position to be eaten and ignored it... If it turns out he's just plain timid, prefers hunting in near-blackness, and only goes for pretty small stuff...boy, I could be in for a really rough ride! :frown:


Re: New octo timid or stressed?|rrtanton|
I can't say for sure, but the light deprivation approach MAY have worked. I curtained off all sides of the tank with towels, and this morning as I took a peek, a portion of scallop I'd left just on top of his hiding place was gone. It would be harder (though not impossible) for a brittle star to get that.

Further, I can't find 4 of my 6 astrea snails, and 2 of my hermit crabs. That may be nothing, they aren't always visible. And I can't see any shells or other detritus.

He is still using the same place as a "den," and I can't see any obvious signs of exploration.

Checking with the LFS, they unfortunately do not have anything that I would consider small enough. I may go there anyway and get a few more blue-legs and perhaps try to pick the smallest of their crabs that I can find. Any comments?


Re: New octo timid or stressed?|octomonkey|
Hi Rusty
I had a good look at the pics and I have sent them on to steve, nancy and of course tony... I decided to reply on TONMO.

I have to say that you have a very nice looking octopus tank and that it is infinitly better looking than many I have seen. I only hope that the fact that this species of octopus is going to be more than likely strictly nocturnal doesnt put you off! :smile:

The octopus pictures were a little blurry but i understand how hard it is to get a pic of them :smile: But from the pics i think i can see a clue as to the species you have and that is the 2 large dark spots on the octopus's mantle. That is a key sign that you probably have Octopus bocki.

Octopus bocki comes from the Philipines and Fiji... Its max size is mantle 2.5cm and arms to 8cm. It normally lives in the branche of coral and is very secretive. Its main prey item is amphipods.

I had an Octopus cf. bocki for a while (cf means 'similar to') and it was hardly to be seen. I had several emails back and forth with Dr Roy Caldwell who has worked with them for a while and he mentioned that there may be as many as 12 species that are all very similar...

anyway, hope it is doing okay. You can buy amphipods online from soem places if you dont have enought too


Re: New octo timid or stressed?|rrtanton|
Heyyy! Now this is interesting...amphipods available online, you say? Those end up being smaller, yes? That might be the perfect size food for this fella. Where might I find them?

Thank you for the comments on my tank! {:-(;D I was hoping it was set up at least decently! I'm very pleased with the live rock I have, and though I'm not sure if I'm entirely happy with the tank dimensions (a bit too narrow in my opinion) it does maximize it's "display" capabilities. That rock eventually started growing very luxuriant macrophytic algae (I should look up the species) which I thought looked great, but I'm certain now that it released something into the water that became a somewhat unpleasant green-brown scum on the surface...keeping the algae in check has cut way back on that problem.

Only possible caveat I'd give about the bocki species tag is that those photos were taken essentially from "behind" his head while he was mostly white. I had assumed those dark spots were actually his eyes viewed from through his fairly translucent body...I don't THINK those spots were actually on the skin. I believe I can see shadows of other internal organs too. When he shows his displays (primarily when reacting to me, as he did this morning when I peeked) he does seem to resemble the photos I've seen of juvenile O. mercatoris on CephBase. I haven't seen him well enough to confirm that though, and I'm obviously new to ceph identification!

Oh, and strictly nocturnal won't put me off, but I'm concerned about his timidity if it means he's going to have difficulty even feeding properly, and curtaining the tank every day seems a rather cumbersome and impractical solution.


Re: New octo timid or stressed?|rrtanton|
News Flash!!!

I cannot say with ABSOLUTE certainty, but I'm 90% sure he just ate! YAY! ;D

The very interesting situation as it happened:

Just befor the lights came on, I decided to give feeding another shot. I first tried a ghost shrimp, trying to wave him in front of the octo with some very long "grippers." No dice. Then I tried a piece of shrimp on the end of a skewer. He grabbed it, then shoved it away...seemed uninterested. Then I tried a tiny piece of scallop...this he grabbed, tugged a bit, and then reeled it in once I gently bumped it off the tip of the skewer!

I'm only 90% certain he ate it since I was doing all this in very dim light in an attempt to make him more comfortable...but I'm sure I saw it being pulled toward the mouth, and I can't see it floating anywhere or on the sandbed...so it must have gone there! Keeping my fingers crossed that this is how it went, I know I could still lose him for whatever reason.

An interesting side note...my most aggressive brittle star came out during this, clearly looking to nab some food himself, so I guess I know where at least some of these pieces have gone.

Might he be just picky about the type of food? Colin mentioned amphipods, and i will look into that. Should I try some squid, fresh if possible? Other ideas? Definitely need to check if there's a seafood supplier in town...


Re: New octo timid or stressed?|octomonkey|
Hi Again

regarding squid - Both myself and Chris Shaw are agreed that squid seems to have 'funny' side effects. With changes in the octopus's personality... are we imagining it? Dunno, but when i fed squid to my cuttlefish they tried to eat each other after that!!! Guess they taste too similar. I have fed squid to octos but some like it and some dont... I am undecided on that one...

As far as the brittle star is concerend I also have a interesting little side note. My brittle star is trying to be the bimac's best friend. It is always within a few cm of the bimac. it has obviously learned that the bimac leaves tasty morsels of food behind iside crab carapaces etc, so it is a constant shadow to the octo which does tolerate the 'friendship' very well. It is actually rare to see them apart unless the octo is actively hunting.

With the splodges on bocki, they are sort of like pigmentation seen through the skin of teh mantle. Not necessarily on the skin but underneath it.

Good work with the feeding, just keep being slow around the octo and keep it dim and try to see what it wants to eat. I am sure that by the look of your live rock you will have lots of amphipods... the octo may be catching them at night... The octo I had that looked like O. filosus was excellent at catching amphipods!

Try looking up amphipod kits on the web or whatever marine sites you look at... maybe try a search on About's salwater forum or Reef Central?


Re: New octo timid or stressed?|rrtanton|
Thanks! Interesting tale about the brittle. I think they're amazing animals. With the nervous system they have, I think it's stunning just watching them move, with such deliberate intent, and your reports of a "learned behavior"...wow! Animals are always so surprising, I'll never tire of them.

Interesting about the species. I'll try to get a good photo, though I think that's going to be quite a challenge as I have yet to see him out of his den and even if I did, it'd probably be a very dim light situation. I'll have to set my camera up and then just keep an eye open.

I've been corresponding with Chris about this actually (Fishsupply recommended I contact him back when I ordered) I'll throw my latest questions out here too.

One, any further advice on sealing a tank? My lid is 2 panels of plexiglass that can be lifted off but otherwise fit snugly (they sit on a "lip") and have gaps cut to allow the pipes and cords access. The lightboxes rest on the edges of the tank over this assembly. I'm considering stuffing the gaps with foam rubber scraps I have from another project, but is that really sufficient? I don't know if I can make an elaborate secure top...are there custom resources out there?

Two...I’m happy enough to have this fellow as a first octo, even if he stays this timid. But the comments I've recieved have reinforced to me that a bimac would be more what I was looking for. I’m aware these guys tend to eat each other...would trying to introduce a bimac be a bad idea, then? I know that in many cases the answer to the question is “we don’t really know, they eat almost anything so we’re afraid to try.” I’m aware of folks who quite successfully kept their octos with animals they shouldn’t have been able to...so I’m willing to experiment if there’s a good chance of success, and I know reporting experiences if valuable to the community. But I’m NOT willing to just let this little guy get eaten just because I’m slightly disappointed with his behavior! I'm happy enough just to have an (apparently healthy) octo this time around. Any experience?

So Rusty
how did it go with your pygmy? I tested my water yesterday and it apeared to be ready so I started making phone calls but it seams like nobody has a bimac so I didnt want to waste any time and got my pygmy I just put it in the tank and it went into a hole in the live rock and its been there for the past four hours from reading your posts I see they are nocturnal whats the best way to give them food and what type of food based on your experience?

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