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Not Another Prospective Newbie!

Mar 13, 2005
Okay, so I've been kicking around the idea of branching out from reefkeeping into a separate (of course!) tank for an octopus.

Although I've done a fair amount of research and learned a lot, I'm probably far from "informed" enough to make me feel comfortable.

So, first question....what about a pie-wedge-shaped 90 gallon acrylic tank for a single bimac?

Any/all recommendations with respect to tank size, maker, purchase source, filter, etc will be eagerly added to the information arsenal.... :rainbow:
HI! A 90 gallon would be a supergreat home for a bimac... Correct me if I am wrong though, wouldn't they prefer a longer swimming space like a rectangle ? I guess a 90 gallon pie would have just about as much lengthway swimming area as a 55 rectangle though, right people? If you measure the length of your 90 and tell me what it is I can compare it to the length of my 55 if you desire?
Hi Siddhartha,

You must be talking about a corner aquarium, right? Although there would be plenty of room for a bimac in a tank like this, they do prefer horizontal room to vertal space. Also, if the tank is very deep, it's harder for you to interact with a feeding stick or even your hand.

Most people are buying their captive-bred bimacs from Octopets or FishSupply.

Have you looked at our Ceph Care articles? Click on the Ceph Care buttons above. I'd recommend the Equipment List, Checklist, and Bimac Care Sheet to start with.

Then if you have more questions, please don't hesitate to ask.

Is it one of the hexagonal tanks that you mean for the pie shape?

A 90 is still a fair sized tank and should be okay for a bimac. So should be okay, but i agree with points made on height vs length/width.

If you can keep a reef tank alive and healthy then an octopus shouldnt cause you too many hassles at all. It obviously produces a lot more waste than a typical reef tank does, so filters and skimmers need to be on the big side. Also tempretures shouldnt be as high as a reef either...

feel free to ask away :smile:
So horizontal length, shallow depth (front to back) and medium depth (height) would be best?

The one I had in mind--best fit for our home--was pie wedge shaped 90g, 24 inches high, about 50 inches ( I think) across the front (IE along the linear length of the curvature, so slightly less in straight horizontal distance)...and the front/back distance I can't recall at the moment.

But if a rectangle would be best then so be it.

If we are going to focus on horizontal width then what about a gallonwise smaller tank (65-75) as long as the 48 inch width minimum is preserved?

I'm thinking a couple of live rock caves (secured if necessary with PVC), but otherwise a relatively open tank interior...to preserve "jet" space and to maximize viewing/interaction area...
I have seen this wedge shaped tank at the LFS - usually in a very beautiful cabinet. The ones I've seen are made to be more at eye level, so the whole set up is quite tall. It's enough room for an octo to swim, but what about your access? Would you have to stand on a step ladder to play "pull the stick" with your bimac and if so, would you mind that? Could you reach the rocks to fish out an partially eaten piece of crawfish?

I believe Carol (corw314) has used a hexagonal tank for some of her octos, but smaller than 90 gallons.

Nancy...actually, the one that I've been eyeballing at my LFS--although I am no means wedded to this one in particular--"ends" with the top edge of the tank at about mid chest for me (I'm 5ft8i), cabinet stand included and with glass top lids (which I know I will have to modify and/or further secure against creature escape and injury).

The corner unit is of course attractive because of the floorspace footprint savings.

The only "hex" units we have seen are of the tall-ish columnar variety. Is that that you mean?

I'm open to designs other than corners. I can certainly see where tanks with access from more than one side would be nice from a visibility and interaction standpoint.

I'd definitely like to keep the skimmer/filtration inside closed cabinetry as much as possible and as little hang-off-tank stuff as possible, too. Lights can be canopied or hooded, doesn't much matter to me.

Thanks again to all you experts out there who are willing to share your insight/experience...
...here's a recent quick morning snapshot of the reef....


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very, very pretty! I kind of like those corner tanks, although I have never used one...the only other problem might be the fact that the tank only has one direction for the octo to look out(ie:he can't look out the back of the tank that faces a window)...but maybe that would be negated if there was enough going on around him...hmmm...could be a neat layout.

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