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Octpus Cyaneus


Pygmy Octopus
Jul 28, 2004
Does anybody have any care guidelines for the Common Tropical Octopus? I hear they are a smaller species whose tentacles reach a length of 6", and that its total span is 12". Aparently, these octopi can be kept in a 30 gallon, hence my intrest! I also need to know where a dealer of this species is. ANY input would be extreamly helpful. Again, thank you....and GREAT site!

I think there must be some confusion here. Octopus cyanea is a larger octopus (body to at least 6 1/2", arms to at least 31 inches) and is found around Hawaii and the Indo-West Pacific region. That means we don't see it here in U.S. much.

It's difficult to find a small tropical octopus on sale here. Since the local fish stores don't know their species. they can't really tell you what you're getting. If you want a wild-caught octopus, spring is the time to try for a young one.

thanks. I guess I should listen to the professionals. Just for informational purposes, this information came from The Marine Aquarium Problem Solver by Nick Dakin. Tanks, I mean thanks!
i have seen that in the book too.

he has his facts all wrong... its not cyaneus its cyanea and as nancy points out his size is miles out!!!

i would class cyanea as a large species
actually, i also saw it in another book...not the same one! it said that they are the most common in the pet trade...i said to myself WHAT? oh, well!
yes there is an octopus cyaneus I actualy have a book hear The Marine Aqarium Problem Solver by Nick Dakin it grows 1 foot tentical to tentical its care guide is just like any other octopus so it says
Clownfish, this just proves that you can't trust everything you read in books. There is no such thing as "just like any other octopus" - different species have different requirements. There are octos that require very cold temperatures, like the ones Jean keeps in New Zealand. There are tropical octopus, and many in between. I have never found a totally accurate description of octos and their care in general aquariium books, even those about reef aquariums.

I've kept a few O. cyanea over the years and they have three things going against them. 1). They do get big. In several months the 3 cm juvenile that you start with will have a 10 - 12 cm mantle and an arm spread of 50 cm. If it has a large tank and continues to grow, they can reach much larger size.

2) They produce huge amounts of ink. and Adult can turn a 200 gal tank completely dark.

3) They bite. I think I've posted before my story of one that got loose on a flight from Hawaii to SFO. Trying to put an unhappy octopus back in a small-mouth container with screaming flight attendants and blood running down your arm makes for an interesting flight.

On the positive side, few octopus can rival a small O. cyanea in the range of colors, patterns and textures that they can assume.

Wow! I didnt know they got so large... When I kept mine I had the very same problem with inking. Almost EVERY time I put them in my tank they inked! I sorta found a solution for this if u are taking them out of the wild. Although u risk losing ur catch its better than letting them ink up the tank. When u catch them u have to milk them for their ink... Sorta. U have to release them back into the water then let them ink and catch them again, and do this over and over untill they have no more ink. As for biting I was never bit. But they were always so weak and timid after that long tramatic fight.
Also, have u ever seen them turn white and black? It's spectacular!
this sounds like a cool octopus what size tank do they need? I now a little about octopus cyanea. I thought they wre to different octopus one small one big what ever
that does sound like a cool octopus
And there was me all happy with my brand new (and first) octo. We have just got - according to our LFS - an O. Cyaneus. And I have to say its absolutly f**king fantastic! It is so active, in the evening before the lights go out, and afterwards, it interacts with me, and it seems so friendly too, and the colour and texture changes are incredible! I was thinking it was clearly an adult, as its reasonably big, but reading all the above, maybe not! But it hasn't inked yet, and does seem happy. It's been eating shrimp, and has made a den etc. Hard to say what the leg span is, as it depends on how far it stretches... but at least 6-8inches I would think.

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