• Looking to buy a cephalopod? Check out Tomh's Cephs Forum, and this post in particular shares important info about our policies as it relates to responsible ceph-keeping.

Need help with set up!!!


Pygmy Octopus
Jun 22, 2006
Hello all, Im new here. Heard about tonmo from reef central. I have been wanting an octopus for several years. I have the guts now to do a set up. I am thinking aout a 65 gal. tank. The filteration is the one thing I can not make my mind up on. I was told that a canister would be fine, but then I think about it and think that is not enough and he will get out. I have thought about a sump,but heard that they will go down into it. I am so confused. To many ideas that I begin to question. That is how I got here. People who love them. As far as the kind of octopus, a mimic is what I would like. Is a skimmer required? I really need help. Hope everyone is ready for alot of questions. Thanks.
Hi Darcy, :welcome:
Before you start asking a ton of question, I suggest you go to the articles and read the ones about ceph care. Many of the questions you have will undoubtedly be answered. by those. Happy reading!:smile:
:welcome: Welcome to TONMO!

A 65 gallon tank should be big enough but Haveing just a Canister filter isnt enough filteration. I suggest A protein skimmer,canisterfilter, and live rock combo because thats what has been working for me. When it comes to octo proofing a sump All you have to do is cover up the overflow box. what an overflow box is pretty much a box that pulls water over the side of your tank and into the sump. people use this to avoid using a pump. a pump. hears a link to help you get the idea:overflow boxes simply cover the overflow with a mesh of some sort to keep the octopus from swimming down the tube and into the sump. As for octopus i do not suggest mimic octopus. There is little that we now about these creatures and even keeping one alive would be extreamly difficult.we arnt even sure if Mimic octopus are endangered or not. there for I suggest a bimac or pygmy octopus. There also are some great Articles on tonmo thyat can be very usful:Articles
Thanks for all the info. I have saltwater tanks-210, 55, 15 tall. FOWLR and eels. I have read alot of the threads and still a little cloudy on some issues. My biggest thing is that I am wanting to give the best enviroment for my new "baby". Correct me if I am wrong but, keeping an octopus is very similar to keeping FO? Just more secure. Water quality and changes should run the same?(right) One more question. How long should I let the new tank cycle, with damsels or not? Thanks.
You can cycle with damsels, just be sure you have a place for them when your ceph arrives because they will not be friends. Damsels like to nip at the eyes. The nitrogen cycle is usually established within a month, but its best to wait a few months for the tank to mature--ie, let all the other chemical cycles and algae blooms run their couse.

You're right that keeping octos is similar to keeping FO. Besides security, the big thing is to consider that a ceph generates a lot more waste than a similarly-sized fish. You want to make sure your system will have a lot of filtration capacity, and be prepared for more water changes as nitrate builds up a lot faster. This is why "reef theory" doesn't much apply to cephs--the live rock alone isn't enough filtration, and a DSB or nitrate coil is just overwhelmed.

How often should I do water changes? How much? In my 210, I am going every 2-3 weeks about 15%. What about RO water, is that a good thing to do? Even though I have had my tanks for about 8 years I still get nervous. I dont want kill or hurt anyone. Im a nervous ninny. I would of thought that an octopus would eat damsels, not the other way around. Good name "DAMNsels". Thanks for the help.-D-
That sounds fine to begin with for water changes. Remember that cephs can grow fast, so just keep an eye on the nitrates and adjust accordingly.

RO water is a necessity. There's enough copper in our salt mixes, we shouldn't be introducing it, or anything else, from our water! Yeah, some parts of the country have really good water, but I don't think its worth it. I spend between $5-10/week buying RO water from my fish shop, which isn't much compared to the cost of feeding my cuttlefish :smile:

That damsels can hurt octos is a big surprise. Reefers have a stereotype about octopus because they can come into their tanks as hitchhikers and eat a lot of things. They do that, of course, but the reality is more complicated. Since they don't have a protective shell they really use their behavior as a first line of defense. If there's something in the tank they're not sure about, they're happy to stay in their den all the time because that's what they're used to in nature. It all comes down to personality.

I agree with the earlier comments about keeping mimcs. Obviously because the animals aren't well known to science and their numbers appear to be diminishing. They don't seem to make great pets, few people have had luck with them. Wild-caught cephs from the other side of the world go through a lot of stress and most end up dying. Wild-caught cephs from around the US seem to make better pets.

There are people around; mainly on RC where the signal-to-noise ratio is so low; who talk about keeping mimics. IMO its the mentality of getting something in a 10 gallon tank for a few weeks to make the dorm room look really cool. Shouldn't keep these things if you're looking for a decoration. That's what freshwater is for :wink:

Hey and welcome to tonmo!:smile:
your tank will take about 3 months to cycle and i would deffinatly recommend a bimac, because mimics are very expensive and possibly endanger. They are also very hard to care for and i believe they need a very large tank. Anyways read the articles :smile:

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