Heinrich - A. aculeatus


Blue Ring
Aug 24, 2011
First Post, my wife and I just got Heini a week ago, he is not shy, and has become accustomed to his new tank pretty quick--the 240 gallon tank is all his(or hers) with a few tank mates
Haven't kept an octopus in 8 years-- and I've missed it last one laid eggs and died--it was pretty big with a wingspan of almost 2 feet trying to figure out how big A. aculeatus will get

Hes eating good --lost the peppermint shrimp, a few emerald crabs, and he's been eating shrimp and fiddler crabs

Located in Lake Arrowhead, CA


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:welcome: to TONMO!

Great tank!

An arm span of two feet is pretty HUGE for a Aculeatus. typically a full grown aculeatus will have an arm length of 7 inches and a mantle of ~2.5 inches.
My last octopus was an Octopus vulgaris--not a Aculeatus-she got pretty big- I don't know much about the Aculeatus--trying to research and find out about them-- its just what the LFS had in the tank-- would have rather got a larger octo--but this one seems cool--thsi octo must be full grown because its longest arms are over 7"--in this picture you can see a damsel fish for scale

As far as tank mates- or dinner--
there are (2) blue damsels---which if I can catch them need to be removed--to agressive toward the octo-- I hope he catches them and eats them--cause I can't figure out how to catch them
(5) green chromis
(2) engineer gobies
(1) coral beauty
(2) clown fishes and thier anenome
(1) sepent star
(6) emerald crabs -- or there were 6 some have been dinner
hundreds of snails, and hermit crabs
there used to be 3 peppermint shrimp--haven't seen them in a while
common shrimp--for food
fiddler crabs for food
(2) sand sifting star fish
(3) sea whips
some corals--bubble, hammer, polys, zoos--nothing expensive

nothing much else

CaptFish;181110 said:
:welcome: to TONMO!

Great tank!

An arm span of two feet is pretty HUGE for a Aculeatus. typically a full grown aculeatus will have an arm length of 7 inches and a mantle of ~2.5 inches.
Welcome Henri!
I avoid damsels like the plague and won't have Chromis again either they are just too wiley and tend to pick on other things. Hopefully the size of the tank will help but with an octo this small, pesky fish are a particularly bad idea. Normally we caution heavily against any fish. The biggest concern is for the octopus and damage that, while not fatal in the ocean, may produced infection that could become a life threatening injury in an aquarium. I would still encourage removal of any that show an interest in the octopus but your tank is larger than most so please keep us informed on how the fish and octopus interact.
I'm amazed, I was looking in my tank last night, and found 3 peppermint shrimp, much bigger than when they were put in the tank a while back
so the body count in the tank is very low, Heini hasn't killed any fish yet, no peppermint shrimp, I keep seeing emerald crabs come out at night, and still see snails all around, and hermit crabs--even the engineer gobies are hanging in there

He has been eating fiddler crabs, and overnight got one out of a jar--or it got out of the jar--didn't see
the marine shrimp are getting consumed i nthe tank, or they are hiding also --we'll see ho long this trend continues

Very surprised how active the octo is in the day time, he seems to go to sleep at night, and flies around the tank all day trying to get our attention so it seems-- he only hides when I'm sticking my arm in the tank to do maintenace of feed some of the corals
Very surprised how active the octo is in the day time, he seems to go to sleep at night
A. aculeatus is a diurnal species so your observations would fit with the ID. The only species of octopus I have kept that would NOT come out during at least part of the day (until senescence) were the two macropuses (they liked 3:00 AM the best and fortunately, while keeping them, I could feed and play on their schedule). Most we see in the trade will at least adjust their behavior to an early AM, early PM routine (crepuscalar). A. aculeatus is the most likely to tollerate other animals. Note the word likely. I have wondered about keeping a pair because of their more docile nature until Roy posted this.
Caught one of the two damsels tonight-- this has been a challenge in a 240 gallon tank with hundreds of pounds of rock
had a conch shell in the tank, and the damsel liked hanging out in it, caught him hanging out near it, trying to nip at the octos tenticles-- then tapped on the glass and he retreated inside-- wife kept tapping on the glass, and I put a net in the tank over the shell opening, and removed the shell, and dumped him in my feeder tank--his new home --one more to go, but the second one doesn't mess with the octo too much
the octo is not mesing with the fish yet, added a starry blennie, and a mimic tang--

had a great fight a night ago, had a marine shrimp from reefs2go.com almost 3" long, Heni grabbed him and fought stirring up the tank, it was quite the battle, then Heni had a big dinner
He doesn't seem to eat everyday like my other Octo did

Heni is much happier minus one Damsel

Found a small mantis shrimp in tank this morning:shock:


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When I discovered Fidel I did not think to look for a mate as I put the LR in the tank. We would hear occasional clicking but still did not put two and two together until after an octopus (Maya) was installed in the tank. Ultimately I tried t rescue the second one and in doing so caused its demise (Maya realized something came out of the LR when I moved it trying to catch the other one and beat me to it). Needless to say, the octo has the advantage, unless the octo is much smaller (as Roy discovered with a Blue Ring several years ago). Sadly, Fidel has recently not come out after his last shed. We have had him over two years and it is sad to look in his little tank and not have him come up to see what I am upto. (if this sounds odd, click IAlex's link :wink2:)
I have been hearing the clicking noise for weeks, and din't discover it was a small mantis until today

the mantis is much much smaller than the octo-- may try to catch it and put it in another tank--we'll see
The mantis I tried to rescue from Maya's tank would hunt at night or at least that is the only time we heard it. Hummelincki's are diurnal so their feeding times were different and it survived until I tried to catch it. I never did see it, I moved the rock, and attempted to capture everything under it with a large net. There was a quick movement to the back of the tank and an immediate pounce by the octo. No more clicking after that. It was really sad because I suspect it was Fidel's mate. I can't say I am a huge mantis fan but I have kept two, one by purchase and one by hitch-hike. Both lived over two years and I will likely look for another to keep.

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