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Looking to chat with blue ring keepers.

Nov 29, 2008
I introduced myself a couple of days ago and was told to post about blue rings in the section. I began a nice message and then my laptop died, completely and forever.

Basically about 2 1/2-3 years back I was interested in keeping octopus as pets. I had collected several magazine articles, including the Coral edition, and a couple of books. While researching a local fish shop owner made an offer to me that maybe we should consider keeping a handful of blue rings. We then both set up 2x 20g cube tanks each and waited patiently for our order. It never arrived. After letting the tanks run without any critters for over a year I went to the coast and caught several sargassum anglers and put them in the 20g tanks. Time passed and the tanks were taken down.

Recently another LFS owner propositioned me, knowing that I had once tried before, about keeping a blue ring. I jumped at the chance and immediately bought an 8g oceanic bio-cube. I had felt that the 20g, as nice as they were, might be a bit large to truly enjoy such a reclusive creature. I then went home and banged out a few pieces of acrylic to completely seal the back area off from the top and glued some plastic mesh over the overflow slits. Once done I added 12 pounds of black aragonite mix and a few choice pieces of live rock covered in zoa, mushrooms, and red macro algae. I let this cycle for a couple of weeks and finally my little blue ring arrived. I've since added more coral and 2 very small damsels and some peppermint shrimp. I was hoping it would eat the damsels and after 2 weeks it had not shown any interest in them. So I then bought 2 peppermint shrimp and sure enough it ate one. It's been yet another week without eating the other shrimp.

Would like to hear what you've been feeding yours. I thought about feeding it emerald crabs or porcelain crabs, but fear their claws damaging the octopus. Not really interested in feeding frozen mysis or silversides as I'm worried about rotting leftovers and I don't care to retrieve any dead fish. I considered live mussels from the seafood shops but have been told they tend to elevate nitrates and phosphates when added to the tank.

Anyways here are some pics.













Ah I just love it, I could post a hundred more but I will stop now.

Anyways let me know what you think. I now have a chiller and plan to drill the back of the tank and plumb in a 50g sump with my Euroreef RS180 skimmer, chiller, and dual inline phosban reactors with Rowaphos and carbon.

BTW-Yes I know how "stupid" this is. Please do not waste my time, the other members time, or your time "educating" me or others about how horrible a person I am. Thanks for understanding. Thanks for understanding the my level of fish keeping and reef keeping are not considered amateur and that without meeting me as a person you couldn't possibly understand my level of experience nor the equipment I keep.


Colossal Squid
Staff member
Jan 22, 2004
You are going to get the rotting leftovers even if you feed live food, so I would come up with an extraction plan.

I would also have a page near the tank of what rescue staff should do if you are bitten (if you are found unconscious near the tank), and a copy in your wallet as well.


Staff member
Sep 4, 2006
One thing Monty did not mention about this thread is that it will not show up on a Google search (by design) and you must be a member to read it. Arguments were heated on how to handle animals whos numbers may be limited in the wild (definitely not the case with this one), their danger to humans or their death rate with importation (the later two being the case with the blue rings). Keeping a thread available to non-supporters but requiring membership was the result of many long discussions.

I am glad you have plans (and I hope quickly) to add the sump. I was going to chime in about the size of that tank and what you already know about feeding and the water (my smallest tank for my mercs is 15 gallons so half that is a BIG concern).

If my dwarf and hummelincki are similar then crabs are a somewhat cleaner offering than you might think (because the the octos eat almost all of the meat but the shell parts do get scattered). I use fiddlers and break off the tips of the large claw on the male eliminating the ability to close it (sometimes it stays attached but most often the crab will detach it). The mercs do not seem to eat the claw meat when separated (I think it may be to difficult to get the meat out as even the attached ones are not fully cleaned out) but my current hummelincki does so if it gets separates, it goes in his tank, regardless of who gets the crab. :smile:. You do not have to worry about the claws on mithrax but in addition to being more expensive - assuming you don't catch your own - they seem to be a last choice (they are eventually eaten and do survive fully submerged much better than the fiddlers) for mine.

As Thales mentioned, you need to find a waste extraction tool for the tank (and he was serious about keeping emergency info visible) as there will be waste that has to be removed but you can reduce it some by including a small thorny sea star. Mine are very active with the left overs and a pleasant addition to the tank. The octo and the star act like they are in two different worlds and ignore each other completely (I have them with both the hummelincki and the mercs and have never had one die). Serpent stars also help out but the tank is so small I think you would find the Thorny ideal and a serpent would outgrow the tank quickly. The only hesitation I have with this recommendation is the mixing of Caribbean and Australian critters and any pathogens that one would tollerate and carry that would kill the other. This is a major problem with mixing Caribbean seahorses with non-Caribbean and even more of a problem with tank bred horses.