Keeping octos together?

[rrtanton]

Does anyone have experience keeping multiple octos together?

Not too long ago, I received my first octo (possibly mercatoris or cf. bocki.) I like the little guy, but I've come to realize this species might not have been quite what I was hoping for--the little guy is incredibly timid and nocturnal. My 55 gal tank has oodles of live rock for him to hide in. When you factor in his teeny size (perhaps 1 inch) which won't change much, you might suddenly realize I have an "invisible" octo! I haven't found his current den over a couple weeks at least, and have never seen him actually moving around--only hermit crab shells show me evidence of his feeding.

I was looking for an octo I could SEE, and I'm realizing that a bimac was probably the wiser choice, as all reports are that you can expect to see them at least every so often! So my thoughts turn to introducing a bimac. BUT...I know enough about octos to know that territoriality and cannibalism are words they know quite well. Has anyone had success keeping multiple octos? Will a large enough tank with enough hiding places make this a safer prospect? I'm very hesitant to callously feed my current little guy to a bigger octo just because I'm disappointed with his behavior. I'm not afraid to experiment, but...I'd really rather inform myself first.

rusty

 

[cephalopoder]

I hear your pain lol. Well I have kept a bimac with a mercatoris (by accident) and the two got along nice until the bimac found the little merc and ate him Soooo that should answer your question. I have always tried to promote the minimum tank size for any octo should be a 30 gallon. But I now feel this is not the case.
Pygmy octos can be kept in something that is smaller. We must be careful of water quality though.
Waste load is something that needs to be watched. It is critical to have a system that can handle the bio load. Octopuses will shoot the levels though the roof of most tanks when first introduced. One octopus can put out 3 times the amount of ammonia as the same weight in fish.
This is why I stress bigger tanks, for the safety buffer.
I kept my mercatiris in a 5 gallon rubbermaid tub bulk headed and plumbed to a larger tank for filtration. I placed a nylon mesh filter bag over the bulk head screen. This system works excellent.
For decoration there were a few pieces of live rock a shallow sand bed and some pvc elbows. The little merc was always visible under red lights at night and I could even feed him frozen mysis from a probe( but man, would he freak out when he touched my finger lol) Cool little octos but they need a specific tank for best viewing I now feel.
A nice little 5 or 10 gallon with a merc by your night stand well filterd and lit by a dim red light would be a awesome night light hehehe.

 

[rrtanton]

Thanks cephalopoder...I suspected something like this. I'm open to other comments too, but as I'm not really interested in setting up a second tank, I'll probably stay pat with my 'lil bud here. I did happen to see him again this afternoon...and not long after he was gone. I missed seeing him move yet again. Drat! At least he's happy in the tank

I think your nightlight idea is marvellous, though I suppose for many people the fear I've heard expressed about "that thing is going to crawl out at night and suck my brains out through my nose" would prevent them from trying this idea.

Grim topic here, but...if he stays this hidden (and given the octo lifespan) how will I know if and when he passes away? Do they tend to float? I'm familiar with the behavior and physical signs a senescent octo exhibits, but it needs to be visible, no? Will a tiny perished octo cause a nitrogen spike in a 55 gal tank?

rusty

 

[cephalopoder]

that thing is going to crawl out at night and suck my brains out through my nose

This will be my selling point...people will stay up to watch this happen lol. That would be a great clip on real tv.
Well the day will come when you have not seen it in months and you will have to take your chance to see if he is gone. If you don't see it die.
Or you could remove all your live rock and see if it cralws out. I did that the first time it got into the main tank lol.