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Octo tank help


O. vulgaris
Oct 19, 2005
Hello. I consider myself to be heavily familiar with salt water tanks. Currently I breed clownfish and propogate corals as a sort of hobby/living. Ive come accross people keeping octopus on other forums, and its really starting to intruege me. I've been thinking about getting a unique pet for some time now, but it just hadnt clicked what to get. I wanted a shark but I'd never be able to support a tank large enough for one(on my income). However I've heard octo can be kept in a much smaller enviroment. I would like to keep it in a tank around the size of a 90gallon, that seems the best but I might have to settle for a 55gallon.

So here comes the questions! (highlighted all the questions :smile: just to make it easy if you dont feel like reading)

What is different about keeping octopus compared to normal reef keeping. What is there to watch out for, and what specific equipment should I rely on? Octopus produce ink when frightened, so should I have a powerful skimmer, maybe go overkill with a couple of skimmers? What temperatures do they like? What kind of fish can I keep in the aquarium with him (I assume very little, maybe really large fish?). What will it eat, I have some very good local fish stores but I really dont have a clue. If I had to order shipments of some sort of feeder fish I would set up a tank for them too. I know I shouldnt keep corals with him, so I wouldnt even try. What kind of lighting and water flow? I assume tons of live rock in the tank.

Any recomended ways to cycle a tank? Assuming that an octopus tank is different and it might need something special. Like high counts of minerals. I'm really shooting in the dark here havnt touched a special creature like this.

I'm probly missing alot... Help me out I really want to get started :smile:
Just a little addition.

I was wondering if its possible to keep more then one in a tank. Not something I'd consider lightly. But contemplating. Just curious really I suppose.

How would you go about buying one? Would you buy it in egg form or a few weeks old? What are good websites to buy from online. I've looked at http://www.octopets.com , but there is only one species. Is this what I want or can I shop around?
squall7733 said:
How would you go about buying one? Would you buy it in egg form or a few weeks old? What are good websites to buy from online. I've looked at http://www.octopets.com , but there is only one species. Is this what I want or can I shop around?

This is the one you want!

You sound like you have the means and the patience to keep an octo!

These articles will get you started nicely,

Keeping Cephalopods in Captivity

Things to Think About Before Keeping an Octopus as a Pet

Bimac Care Sheet

Equipment List

Ink's Story

Keeping an octo can be as difficult as you want to make it, previously I would run a simple set up with LR, low lighting, a few power heads, prism venturi skimmer, and basic HOB filter... But after learning to keep a reef tank, I plan on running my octo tank just like my reef, well sadly better. Or good... not sure. Using 2 x 65W PC retrofit, 40-60 pounds of Reef Grade Substrate, 50-100 pounds of LR, for a 40G tank. I am using that agrecrete method for the bulk of my base rock, as suggested by www.GARF.org to preserve the natural oceans. Sump/refugium, in tank overflow and such, my point is you have plenty of experience it sound like in tank set up, so run what you would to get a good tank, water quality is everything in a reef and I like to keep that going for a octo tank. Your skimmer should be overboard, however you only do need one, just get one rated for say 100G for a 55G tank, if you keep a Bimac from Octopets, a 55G is perfect. Any fish you keep could get eaten, I kept 3 damsels with my Octo and he was never able to keep them since they are bottom dwellers, the fish are a challenge to keep, mine ate the fish once I took out all the LR and the fish had no where to go since I also took most the water out of the tank/displacement. But I would not keep any big fish, not even medium sized, and if it not reef safe defiantly not. I had a huma huma with an octo, and literally scared the octo to death. Water quality should be kept the same as a normal reef tank; salinity should be a little higher, with a SG of around 1.025 or so. Temp the lower the better but you should not need a chiller. 72-80 is acceptable but will shorted the life the hotter it is. Flow should be about 10x the tank capacity, lighting is up to you, don’t do MH though, but Bimacs are shallow water species so they can tolerate enough light to grow some xenias, and shrooms and such, no acrapora, since that requires MH... right? Feeding them is expensive, feed only marine animals, no freshwater. Fiddlers, shrimp, clams, are best sources of energy, live food only when young, and if you can afford it, ALWAYS. It can be collected from the local beaches if you’re on the coast. Cycle as normal, toss some damsels in there to get it going, wait a while fro the skimmer. Run a refugium w/macro, to control the nitrates... Most people don't seem to, cause they use skeleton set ups but I prefer my tanks to run them self, I still maintain like they are helpless but its nice to know that if you miss a water change your going to be fine. Sorry my post is all over, but I was not really in the mood to sort out my info and type it in a good order, kind of scatter brained atm.
Hi Squall,

Heere are a couple of more sources of info for you:

Sorry, that's a dead link (404)

Sorry, that's a dead link (404)

While there are several species of octo that have been successfully kept in home aquariums, there are a number of advantages to getting an O. bimaculoides from Octopets:

1. You will know what you're getting - Unfortunately quite a few octopus sellers are dealing in wild caught animals of doubtful species. Not knowing the species can seriously affect your chances of success! [For example, Bimacs prefer a temperature that 10 to 15F cooler than the truly tropical animals that most reefers keep.]

2. 'Bimacs' are almost certainly the most commonly kept species and that means that it's also the best understood species in terms of home aquarium husbandry.

3. Since Octopets deals in captive bred octos you'll also have a pretty good idea of what your new octo's life expectancy is. Keep in mind that octos are very short lived animals - Bimacs live about 13 or 14 months; the so called pygmy species live half that long; and even the Giant Pacific Octopus only lives about 3 years.

A couple of other comments:

Using the "Aragocrete" as Travis suggests will also give you the oportunity to incorporate any number of den sites into your rockwork. OTOH: A lot of folks think that aragocrete is a singularly ugly looking material until it's had enough time to recruit a covering of coraline algae.

I wouldn't try keeping two octos in the same tank unless it was a very large tank such that the two could establish completely separate hunting territories. I believe someone on this forum has kept two bimacs in a 120gal for a while but I'm not sure if they stayed there through maturity. The thing is that when two octos meet they either mate (if they've reached that stage of life) or the bigger one eats the smaller. There is also a good deal of anecdotal evidence of the female eating the male immediately after mating; in fact, I think that I saw a video of this somewhere on the TONMO site.

Don't worry too much about lighting - these aren't corals! Most species of octos prefer pretty low light levels and many of them (most?) are naturally nocturnal. Many people though have been successful in convincing their own individual octo that it's OK to come out in the "daytime".

Suggestively yours,

Thanks for the great replys.

I'm convinced I'll only keep one now. I know the lifespan is short and I'm sure it will hurt in a year or so when he bites the dust. But its only natural, I'll just have to get another one when it happens and start all over again. I'm prepared for that.

I acctualy have some experience with agrocrete. I usualy make different pieces to put my coral cuttings on. I have no doubt I'd be able to make some pretty nifty caves for the critters. I'll probly use double actnics for lighting as that seems to grow coralline the fastest.

I was wondering how big a octo. from that website usualy is when it is shipped. I've been reading that many people use pvc pipe to house its home. I can do better with real caves. But I dont know what size to start with, and what size to finish with. I'm seriously looking at a 90 gallon now. How big will he get in a tank that size and relative to his size how big should his cave be?

Also I was reading a bit on RO water. Some people suggest to use normal tap water(treated first of course!) because the octo will benefit from the various minerals in the water. And that RO water is TOO pure. Anyone have an opinion on this? I'd rather go tap water myself but if RO water imrpoves his life I'll do it.
Reading all these octo stories is really getting me excited about it. I cant wait to get started as soon as I can get some funds together to buy and put the tank up. I hope to have one around christmas! :smile:

But I'll still need everyones help here. You guys have been great providing me with the information I need and I still have questions... (like the ones above :smile: I know I just had to make another post after reading that story about Ink the octopus)

I'm hearing they arrive in sizes up to a quarter. Thats pretty tiny, how big do they get and how fast do they grow, in a 90 gallon. My biggest concern is thier diet. I hear that they will eat any type of sea food. What do you feed it the first month of its life. Clams? And when they sea any sea food , could I go to a market and buy whatever salt water fish they have in stock, cut it up and feed it to it in moderation just like that? Will that keep it healthy.

I was wondering what you do about cleanup crew. I like to keep hermits and snails to keep my tanks clean, but that wont do. Are there certain species that will substitute for this tasks that Mr. Octopus wont eat?

Wow I have so many questions lol. I'm sorry I hope I'm not being a pest.
squall7733 said:
Also I was reading a bit on RO water. Some people suggest to use normal tap water(treated first of course!) because the octo will benefit from the various minerals in the water. And that RO water is TOO pure.

I'd say this is BS. Always use RO+DI. The EPA's drinking water standard for nitrate, for example, is ~30 mg/L. Try doing water changes with that! I don't think the treatment would take out all the copper or dangerous things in the water. Plus, the thing to think about when adding a treatment is "shouldn't I be taking chemicals out of the water, rather than putting them in?"

What minerals you find in your tapwater are controlled by the rocks and soils that the water flows through before it reaches the aquifer it's pumped out of. The minerals in the octo's natural habitat, however, are mainly controlled by the chemistry of the ocean and possibly a little tiny bit by the minerals found in runoff. I don't think you can assume that the minerals in your tapwater are the same minerals beneficial to the octopus.

DHyslop said:
What minerals you find in your tapwater are controlled by the rocks and soils that the water flows through before it reaches the aquifer it's pumped out of.

And, of course, whatever piping is between the water company and the tap. If you have copper piping in your home, for example, it would seem like a terrible idea to use tapwater.
Okay. I think I may have gotten my information a little wrong on that one. I've been reading alot of articles on octopus and starfish lately and I think the tap water thing came from a starfish article. I'll invest in an RO unit.
I was drawing up sketches for my setup. Wondering if its wise to put the heaters acctualy inside the tank or should they be in the sump? I want to put a couple cooling fans on the sump so I can keep the temperature as low as possible to extend the life spand of my new pet. With that kind of set up it seems reasonable to put the heaters in the tank, if it gets too cold theyd just heat it up. But with an Octo tank I really dont know what I should do. Will it play with the heaters if I decide to put them in the tank?
Most people don't need a heater with a bimac. Bimacs can tolerate cooler water - in the 60's is fine. If you're going to use a heater, put it in the sump and set it quite low - the fan will bring the water down a few degrees but not enough to cause the heater to come on.

What she said !!! :smile:
The less stuff you have in the tank, the happier you and your octo will be, anyway...the curiousity factor is intense with these critters!!
Glad you got the RO thing sorted out...almost all of the ocean salts have the correct proportions of metals and minerals already in them...and with the huge amount of crap in the tap water these days (we don't drink it), it is best to avoid it like the plague.

One thing I forgot to comment on is the amount of live rock. Sometimes you'll hear a pound for every gallon, sometimes 1 1/2 pounds or more. My experience has been that 1 pound per gallon is quite enough for your aquascaping and to provide dens of various sizes. More live rock begins to take up too much space and get in the way of the little "beach" where your octo can play and the swimming space he'll need. I found there was quite a bit of jetting, swimming, "romping" and moving around over the whole tank. I actually ended up removing a few rocks!

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