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Bimac or Vulgaris?

Jan 15, 2004
I've browsed many of the pages to gain some info about getting an octo, but still have some questions I either cannot find the answer to or found the answer to in many of the discussions but forgot and don't know where to look again.

First off, my tank is ready for an octo. There's plenty of live rock/sand. All that remains in it is a snail, some hermits, a cucumber, and a damsel (I've removed all my other inverts/corals).

I've been reading up as much as possible as far as which octo to get--seems it's either a bimac or a vulgaris. I've noticed that the majority have bimacs or at least recommend bimacs...Is there a reason for this? Obviously, I would like an octo which wouldn't constantly hide in the live rock, but interact (during day and night). Do bimacs offer this compared to a vulgaris?

Another question... would getting a tank-raised octo be preferred to one caught from the wild. The LFS near me has a baby vulgaris that was "most likely" caught from the wild. Does one acclimate better than the other? Would one likely be more active in a tank compared to the other? And as far as feeding, do tank-raised better take frozen food compared to wild caught?

When I do get an octo, I'll be taking the damsel out, but wanted to keep the cucumber in there. Is this OK? Also, can any other inverts/corals be placed in there at the time the octo arrives?

Hope no one minds all these questions...and I'm sure some may overlap questions previously asked, but just can't find the answer for. I just wanted as much info I can get before actually getting the little guy.
Bimacs are better as they are not escape prone, but vulgaris on the other hand are the opposite.

Tank raised specimens are definitely better as they are very likely to feed, don't have parasites that might kill the octo. They are also more friendly and you will be able to know more about that octopuses history. Thay also take the pressure of wild caught species. :smile:
As far as i can tell the cucumber would be fine.

Bimacs are also dinural not noctural, so depending the hours you are at home may answer your question.

If you have a lot of live rock good luck on the damsel, how do you plan on getting 1 fast little bugger out? :P

Most corals should not pose a threat to octos but keep in mind the lights that corals require are no where near wghhat an octo need. Flourences are fine for octos. Aside from promoting undisreable algae groth they are not neccessary.

You would have to be more specific on the types of corals/inverts.

Keep in mind all of you rock /corals must be securly placed(glued) unless you dont mind a creative interior decorator when the octo arrives.
That's why the damsel is still in there!! Damn fast little sucker! I'm borrowing a few of my friends nets, so I hope to trap him in a corner so he at least cannot get to any of the rock!

As far as the inverts, I was mostly concered with the cucumber, some feather dusters, and ricordia mushrooms. I just adjusted the tank so it only has one 50/50 actinic light (going 7 hours during day) and then at night has moonlights. I hope this will be OK for the octo.

The pieces of live rock in there are fairly large and pretty much secure. I do have some other shells and such that the little guy can have fun decorating with.

The tank is 40 g. and from what I've been reading, a bimac might be better just since a vulgaris can get much larger.

I'm going to be checking the water again this weekend, and if I can get that damsel out, I'll most likely be ordering a little octo at the beginning of next week! :heee: :heee:

It seems as though most recommend octopets or fishsupply, so I'll check out both of them!
I would highly recommed a bimac with that tank size and it still will be on the tight side eventually.

Is your damsel agressive towards other tankmates? Is it larger? If not he might become a meal if not to territorial. However, removal is your best option. Especially if getting a young captive bred bimac - 1" mantle.

Your corals and lights sound ok. Still a little much for a octo.
I wish I had a larger tank at the present, from what I've been reading. Prior to viewing info on Tonmo, I was told a 15 gallon and up was OK. Obviously this is not the case!

I've had this damsel for three years now and I just can't seem to have him be used as a meal. It's a bit larger and seems to be territorial only towards new introductions. In any rate, he has a future home in my other tank. I just need a few extra hands to work the other nets as well as some "stealth-like" moves!

Everything will be out of the tank except for the live rock, cucumber, and hermit crabs/snail (as well as some macroalgae). At this point, I won't look to adding more until the little guy gets adjusted. Do you think the lights are OK? WHen I switched it from the two lights to just the one 50/50, it surely didn't seem as bright, but is it actually too bright?

I know the moonlights just put a soft glow on the tank, nothing bright at all.
Hope you find enough help for the damsel as he sounds like he needs to be removed regardless before your octo gets there.

The lights should be ok, just try to discourge aglea growth. It just means less chance of extra cleaning and work.

I can not honelesty say much about somewhere you coming accross the info that a 15 gallon ok for a bimac much less a vulgaris. That may be fine for the beginning but plan on getting a bigger tank quickly if you went wit ha 15 gallon.

A 40 may just be fine for a bimac. I would rule out vulgaris. Try to keep him/her on the smaller size by regulating feeding.

The old rule of though was 30 gollan was fine for a bimac, but it seems, with help like forums such as this, that 55 is a lot better.

There are several reasons why: more water incase of a foul up, more dispersal of ink which is not toxic to octos unless in small spaces, etc.

Which brings up more questions and concerns considering your last inquiry in tank size.

What kind of filtration and skimmer do you have going?
Have you tested for Copper or phosphates in your H2O?
Hi Octopussy007,

You don't really need actinic lights with an octopus. One 30W fluorescent will do just fine. Is your actinic light suspended above the tank like a reef tank? If so, how are you going to secure your tank so your octopus can't escape? (And even bimacs try to escape.)

I hope you've taken a look at two of our Ceph Care articles, Colin's Equpiment List and my Checklist. There is a lot of good information there.
(Click on the Ceph Care button on the top of the home page to find these articles listed.)

Your octopus will evenually regard everything in the tank, dead or alive, as part of the aquascape that he can rearrange. They have been known to snap off featherdusters, turn large rocks upside down, and move pencil urchins. Even corals that are glued are not wholly safe.

A vulgaris would need a very large tank because of its size. We're recommending at least a 50 gallon for a bimac, larger if you can do it. I kept my bimac in a 46 gallon tank, and she was cramped when she took up jet swimming. Also, I had to do a lot more water changes to maintain the water quality.

Many bimacs do jet swim and seem to take it up when they're adults. My bimac was wild caught, so I can only estimate her age when she did this: I think it was when she was 10 - 12 months old. (She laid and watched over her eggs in the two months after that).

They don't seem to try this if they're in a tank which makes it very difficult (like a vertical tank). And of course, bimacs are not the only species that jet swim.

Thanks Nancy.

I am cycling a tank for a cb bimac right now. :biggrin2:

And I was curious if it is a activity they do early or more in adult stages.
I am sure cb and wild caught are different to some degree in this.

My tank is a 55 gall with lost of "swimming" room as well as hidding places.

Am planning on getting a pic of it this weekend if possible.

Thanks Again!!!
We'll look forward to seeing it!

Several of us are working on timelines showing our bimacs' activities at certain points in their lives. Sounds like this might be helpful. Don't know that there's a big behavioral differerence between captive bred and wild caught.

i wouldnt expect there too be either but perhaps less trauma during capture from the wild does make a difference? Perhaps this is why some octos are shyer than others? Something that happened when they were a larvae?
I would expect a wild caught to be a bit more timid and shy compared to a cultured and bred octo.

It would be similar to purchasing a bred dog from a breeder or stray wild dog found in the forest. Usually the bred dog is more adapt to "pet" life. No???

Nancy, the light is underneath the hood with it's own covering. At this point, i've made sure the tank is as much escape proof as possible. The hood, pipes, pumps, filters, etc. Thanks for the advice about the Actinic lights. For some reason I thought that would be better than a regular fluorescent that was also in there. Right now there is only one of those coralife 50/50 bulbs (just one bulb) connected. Should I totally have no actinic and replace that with just a fluorescent? Either way, there will only be the one bulb on during the day.

The moon lights go on right after the day lights go off (around 6ish). How long should I have the moon lights set? I have them placed so they don't "point" straight into the tank, but reflect off the top of the hood to make a subtle "glowing" effect. I hope this won't be too bright, as it doesn't seem too bright at all.
Flourences would be best. As bimacs are dinural they need no light at night. The moonlights would be almost specifically for your mood, or time you want a little tank action and not\ darkness.

It would be up to you, but in my opinion, octos really only need moonlights if they are nocturnal. Like mercatoris for example.

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