Pygmy Octopus – 06/15/07
I've always wanted an Octopus in my aquarium, I think It would be a very nice touch. But I also know that if I purchased one, it would eat all of my fish. Would this be true if I obtained a pygmy octopus?
<Likely so... if it was much smaller, itself might be a meal...>
Its small size makes me wonder if it would pose a threat to any of my fish, but I just wanted to ask you guys.
Thanks,
-John
<Do take a look at the recent issue of TFH... Dedicated to Octopus husbandry... and the few excellent Cephalopod, Octopus websites... Bob Fenner>

Re: Octopus care/capture & Brittle Star comp. 1/29/07
Good Evening and thanks for the insight.
<Welcome, Jim.>
I am sure that it is an octopus.
<Have you had a chance to peruse the archives on octopi snaring techniques?>
We have seen it 3 times but it hides very fast. It is about as big as my hand if it is all spread out.
<Neat, but unfortunate.>
My concern is I can't figure what it is eating (or if it is eating).
<What are it's options for motile invertebrates in your setup? If there is not food, then it probably is starving.>
I would hate to have it die. I again tried to search every piece of rock with no luck.
<I'm afraid that is going to stay the case until you: A) see which rock he enters and remove it, or B) Try to "snare" it using bait and a trap. The units I've seen are like the ones used for mantis shrimp: A clear tube with a manual trap-door that you wait patiently over. There may be more advanced designs available that I am unaware of as yet, but...>
If it does die and I don't find it, won't that be a big problem?
<Could help the cycling, but I'm going to stick with a firm "Yep." Don't want that to happen.>
I have also left pieces of shrimp in over night but they have not been touched.
<Hmm... how about a crab or urchin or something that moves? They are very opportunistic feeders, and would probably love a crabby-snack. Put one in a tube and you have a craburrito! Yum!>
Any advice would be appreciated. On another topic: There are many small brittle stars. The largest is about the size of a half dollar (including arms).
<These may or may not sustain your hitch-hiker...>
They are too small to bother anything I am sure but will they bother polyps or other soft things when and if they grow?
<Not really. They will close up as the stars lumber around on them.>
There are now 2 colonies of polyps as well as many small feather dusters. I read that brittle stars can be destructive as they grow.
<Can be destructive, depends on the species. Have been told (by Rick O.) of a green serpent star "tenting" in wait and when a royal Gramma went near, the unlucky fish was caught and eaten. Actually, maybe it wasn't a Gramma, but... you get the point. I wouldn't worry about the corals' safety, though.>
We almost don't need a television anymore because the family all congregate around the aquarium to watch
and see what's new.
<I know exactly what you mean!!! Best wishes!
-GrahamT>
Thanks again.
Jim

The Nature of the Beast... Carib. Octopus... beh., comp./removal   1/27/07
Bob,
<Scott>
About 4 months back a small Caribbean octopus made it's way into my clients 1300g reef tank.
<"Made it's way...?">
I was unable to extract it,
<Nearly impossible...>
and assumed (/hoped) it dead due to unsuccessful Octo hunting adventures, and a lack of missing livestock.  There was an unfortunate heat spike soon after he was introduced, in which a good chunk of the more sensitive corals died, so it made sense that he may have made his final bidding as well.
Until just recently the has been very lightly stocked.  Lots of cleanup crew and maybe 25 fish or so, only one over 3", which was a big 10" Naso Tang.  Since that time we have lost only two fish - a 3" fairy wrasse and the big Naso which came as a huge surprise.  One day he was fat, healthy, and eating perfectly and the next day (maybe two, I'm only in every few days) he was a pile of bones plastered to the overflow.
<Oh oh...>
There are also about 4 Pacific Skunk Cleaner Shrimp missing, and I've never seen any of 8 small Mithrax crabs I put in there.  
<I don't need to see another Powell/Loy film to see what's coming>
There were 18 peppermints originally as well, many of which are to date clearly seen, but never countable.
Just within the past few weeks we have started heavily stocking the tank, and given certain circumstances that have come with that stocking my suspicions to believe the Octo may still be on the prowl have risen.
<If it's there, of a certainty>
So what I'm curious about is whether your garden variety Caribbean octopus is strictly a shoot to kill type predator, or willing to damage fish and potentially give up and move on.
<I think pretty much the former... sizes up prey and only attacks if likely to win>
And if they did do such a thing, what would those marks look like?  
<Bites and scrapes... empty skeletons...>
What sized prey is an Octo generally willing to predate upon...would they go for a fish that was say 2, 3, 4 or potentially even 10 times it's own size?
<Smaller is likely preferable... From what I've read and observed in the wild, Octopus species would rather eat a few to several less-likely-to-damage-them prey than tussle with something too big... And as the common notion goes... they are "smart"... do understand the size, shape of the world/system they're in, what is in their with them...>
And finally, in 4 months could a small Caribbean octopus survive off of 8 Mithrax, a 3" fairy wrasse, 4 Skunk Cleaners, perhaps 5-10 Peppermints, and a hearty chunk of a Naso Tang.
<Yes, I think so>
Moreover, even if he could survive on that much... would he not have eaten much more with a smorgasbord of fish and crustaceans right at his tentacles?
<Mmm, no... not necessarily. Have witnessed a wide mix of selective predatory behaviors with individuals of this genus, species... not at all predictable in my estimation>
I apologize if the whole query seems simple, because I feel like I'm asking stupid questions with obvious answers and I know your time is valuable.  I appreciate your input.
Scott
<I do wish I had a sure-fire suggestion for removing this animal... I would try baiting a "snap-lid type trap" (e.g. the all-plastic rodent ones sold for marine use...) baited with a small local/Caribbean live crab (almost irresistible to these)... to remove it, stat.! Bob Fenner>

Removing an Octopus from a large aquarium   9/27/06
Bob,
I've got a fairly serious problem. A small Caribbean octopus "found" it's way into my clients 1300g reef tank. Obviously, I need to get it out. Any suggestions?
Thanks,
Scott
<Mmm, yes... a barbless hook and crab bait... and be ready to get into the tank after hooking... and to remedy the animal inking the system. It's either this or dumping the entire system and dismantling the decor. Bob Fenner>

Bimaculoides Octopus and Fish - 8/20/03
Hi WWM crew,
<howdy>
Thanks a lot for taking the time to answer my question. I have been reading a lot about the cephalopods and the Bimaculoides octopus in particular.
<a very good species choice>
I have a chance right now to buy a very young tank-raised baby Bimaculoides that has a head that is about the size of a small gumball. I was wondering, if this octopus was raised and fed only frozen foods or small crustacean as his diet, would he be able to live along with the other fish in my 80g tank?
<not at all... it is unrealistic to expect to conquer natural instinct and thousands of years of evolution just by hand-rearing>
None of my fish are aggressive and I have a good amount of live rock with caves. Right now I have a medium regal tang, a flame angel and a small long nosed butterfly fish and two clownfish. Would these fish be able to live with the octopus in harmony?
<actually... your tang, angel and butterfly will almost certainly nip at or eat the baby octopus. Quite certain. Read and research more... you will understand that cephalopods simply must be kept in species tanks only>
Thanks again, Rocko
<best of luck, Anthony>

The Octopus and the Moray
Hi Bob,  
I have a 30 gallon marine aquarium. I have on bimacluoides octopus (1 inch) in my tank alone. In my 10 gallon marine aquarium I have one snowflake eel I am quarantining. The eel is about 5 inches. Is it okay to mix these two together.
<Mmm, no... though the moray you have feeds most often (in the wild) on crustaceans... it might very well bother the Octopus to the extent that it inks your system... likely deadly to both>
I feed my marine life 2 times a day so would there be a problem with food? Or do you think I should put the eel in the 30 and the Octo in the 10? Please get back to me as soon as possible.   
<I would go with this last plan... separately stocking... DO keep your tanks completely covered! Both these animals are very adept at getting out of tanks. Bob Fenner>   

Octopus Love: 
can I put anything in with my octopus or will it kill it. can I put coral or live rock in it?
>>
<Most systems with most Octopus species/specimens do fine with coral and live rock... The cephalopod needs the coverage/habitat, and unless its stressed to the point of "inking" its environment will generally leave all corals alone. 
Bob Fenner>

Octopus, mix in small aquarium
Can a small octopus live in a fish and invertebrate tank with fish not bigger than him, but he is not bigger than the fish?
<Not a good gamble... these intelligent mollusks can be very touchy in such a setting. What if it "inks" the tank? How would you feel if it ate its tankmates... yes, even though they're bigger than it? Please read over the sections starting with Mollusks on the site: www.wetwebmedia.com.
Cephalopods are best maintained in designated "specimen" tanks... or public aquariums. Bob Fenner>

Nautilus
Do you think it would be safe to keep a nautilus in a
240gallon tank with fish like a Sohal and emperor
angel? would the Nautilus be able to catch these fish?
the nautilus' ability to catch fish is my main
concern. Can it? thanks
<More likely the fish would bother the Nautilus... best to keep these cephalopods in their own, dedicated system... with low lighting... good filtration... Don't think this mollusk would catch these fish species... unless it was exceedingly hungry. Bob Fenner>

Octopus
I want to put a shark in with a octopus I was wondering if the shark would eat the octopus or octopus would eat the shark?
<Either is possible depending on species, but the mix is a bad idea regardless. -Steven Pro>

Moray eats crabs (and Octopus? News at 11:00)
will the snowflake eel eat a octopus? <<It could, given a lack of room to get away. Eels are one of the big octopus predators.>> & how big of a tank does it need <<It which? The eel or the octopus? A snowflake could probably do well in a 75, a 55 at a bare minimum. An octopus could do fine in less space, but no matter what you choose, you would need a top that it pretty much nailed onto the tank. Both the eel and octopus are expert escape artists, but the octopus is perhaps a genius when it comes to getting out of tight places.>>
thanks
<<Cheers, J -- >>

Eel eats Octopus Read all about it!
Luc again will the octopus eat the eel?? thanks
<<Hello, I just replied to your original email. Again, my answer is a qualified yes - eels do eat octopi in the wild. Can it/will it happen in a captive system - depends if the octopus has room to get away, although if it deploys it's ink as a get-away mechanism, you will have some problems on your hands. I wouldn't house these two together. Cheers, J -- >>

Moray eats crabs (and Octopus? News at 11:00)
Oh boy... did I screw that up? I was sure I had read somewhere, and seen
video footage of an eel spinning around and around while it bit off an
octopus tentacle. Octopus lived, but eel got food for the effort...
<Saw the same footage I think... Australia if memory serves...>
Am I wrong? I'll gladly post a disclaimer...
<Not wrong at all... these animals are as compatible together as you and I living in a pizzeria! B>
J --

Octopus compatible fish - 2/16/03
I wanted to know if you can recommended any compatible fish that will live in the same tank as my octopus without it eating them?>I currently have 3 cleaner shrimp with the octopus and they are doing fine. Thanks, Michael Casillas
<To be responsible... we do not recommend anything with an octopus. Everything is either prey or predator to an octopus. My guess is that your cleaner shrimp have only been with this octopus for a matter of just a few months... perhaps even weeks. They will not live to see a year if the octopus is healthy and that's a gross understatement. Please do remove the shrimp ASAP... they are a natural prey item. To solve your dilemma... let me suggest you create a dry or wet (with fishes) diorama display tank behind your octopus tank. We have seen some outstanding presentations made this way. It encourages the octopus to hang out on the glass too,  salivating over the fishes in the next tank <G>. Best regards, Anthony>