• 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.

Getting into fish...


Apr 11, 2003
Hi. I've been reading a whole bunch of stuff (on this site and others) about how to care for an octopus. I am really intrigued about having an octopus but every site that I go to says that they are for experienced people only. My problem is that my experience with caring for fish is the same as my experience with piloting a space shuttle (non-existent.) So I have a pretty good feeling that if I ordered an octopus it would die within a day :| . So instead of killing a perfectly good octopus I think I'll take everyone's advice and get some experience first. My question is what would be a good starter fish? I was kind of wanting something more intelligent than a gold fish (do they even HAVE a brain??? :bonk: ) What would you guys suggest?
Hi Molson...welcome to Tonmo! :biggrin2: (don't worry if some of the residents appear a little strange...I, of course, am perfectly normal...:cyclops: )

:grad: You may not even have to use fish, depending on your preferences. If you want your tank to be an octo tank eventually, you'll have to remove those fish at some point down the road, or accept their ultimate fate as dinner! :twisted: Further, you'll need to consider your initial selection of fish--some are potentially threatening to an octo.

I started out with invertebrates...some urchins, brittle stars, snails, etc. I decided to get a "lettuce slug" nudibranch (a type of sea slug, if you're unfamiliar with them) as a "test animal." I figured it would be relatively delicate, and as close to an octopus (they are all related--snails, slugs, clams, oysters octopus, squid, etc.) as I could get for a low price. He did just fine in my tank...uh...that is...until I accidentally removed him when pruning my macryphytic algae... :oops: Well, he WAS fantastically camoflagued... Anyway, after that, I knew the system could handle an octopus.

Biggest secrets to my success were research, the use of plentiful, high-quality live rock, and a general conservative approach--I cycled the tank longer than necessary with my live rock and sand, just to be sure, and I added animals SLOWLY, one at a time, with a very low overall bioload--the tank could easily handle twice what I've added. With this approach, I found keeping the tank to be EVER so much easier than I thought it'd be.

Now, with all that said, I suffered a major tank crash a bit more than a month ago. I had (for my and the tank's safety) plugged all the equipment into a GFCI outlet, which tripped while I was on vacation for a week during thunderstorms. This killed some of my animals, including my octopus, up to that point a happy resident for about 5 months. If I'd had more experience as an aquarist, I'd have known this was a risk, and would have taken appropriate measures to prevent it. I also regret not setting the system up with a sump from the beginning, which I'm now building. So, don't feel silly about wanting to take your time. You can probably have an octo on a relatively short schedule, but it will definitely raise your risks of an accident here or there, which could prematurely scare you away from this wonderful hobby.

Now, one more little secret...the reason I spent so much time talking about the way I set my tank up is...I don't know a thing about keeping vertebrates! But don't tell anyone, okay? :wink:

wow... now that you put it THAT way...

I guess I don't have to start with an empty tank and a piece of seaweed after all :P

I guess I could do what you did, but the reason I wanted to get experience first is because when I hear about how strict you have to be about what is IN the water, I have no clue about what kind of equipment I need, or more importantly, how to operate this stuff!!!!! For example, I hear that some people have computer programs that monitor the different "Stuff" in their water. Do I need something like that???? And here's the really noob question: how do you make salt water!!!! :?:

Perhaps I worry too much. But I just want to make sure that I don't jump into this with both feet and realize that every thing I have done is totally wrong. So you say you used urchins and other types of fish? So what one of these would be a good starter? And how big of a tank would I need? And more importantly, am I going to have to set up my aquarium so that I look like some mad scientist??? :madsci: (I hear that you need to have a "hundred" different contraptions hooked up to your tank. Fact or fiction??)
Hi Molson

Welcome to tonmo :smile:

Well to be honest there is a lot to learn and starting with marines is more compicated than freshwater but not impossible. The key is to read around the subject and post any questions you have here.

Dont know if you seen it but I have compiled an equipment list on tonmo.com here... Cephalopod Care and it covers everything you will need to start out.

For example.... The salt needed to make your water into seawater is bought by the packet or bucket from an aquarium shop or online and is specially formulated to be as close to sea water as possible. You test it with a hydrometer to make sure that it is holding as much salt as the sea normally would at the same temperature.

try to start with as big a tank as possible. The larger the tank the more stable it is. so aim big... look at over 35 gals anyway... It costs more to start with but is EASIER! :smile:

also, you can make it look like a scientist's lab if you want to 8) but it can be as simplistic or as complicated as you like, but there are some things that are esential so have a read at the list and let us know what you need to know :smile:

Ah...that gives me a better idea of the sort of info you're looking for...

I decided to buy into a marketing gimmick and get the book "Saltwater Aquariums for Dummies," by Gregory Skomal. Was at my local Barnes & Noble, could surely be ordered through Amazon (and if you do it through the Tonmo.com link, Tonmo gets credit! :biggrin2: ) Anyway, I found this a very comforting, handholding, simple but adequately detailed book, precisely what I was needing for setup.

I used a modified version of his recommendations--the critical "equipment" for my 55 gallon tank is 50 pounds of live rock, some live sand, protein skimmer, canister filter, and then just various sundries...a few powerheads for circulation in the tank, lights I built myself to feed my corals. I balked at buying an expensive water prefiltration system (you need to add very pure water to your tank, and the best available is reverse osmosis/deionization) and found that I could get away with a cheap homebuilt system involving a Pur faucet-mounted filter and a PVC pipe with a PolyFilter stuffed into it. That's the short version...eventually I'll get an article finished talking about that for the website.

Money is always an issue, but...if you haven't bought a tank yet, you may really want to consider a "package" deal from a good fish shop, depending on what's IN the package. You can get a stand and hood appropriate for your planned uses, and you can get a predrilled tank complete with sump--that would allow you to have a much more convenient sump from the beginning. I didn't want a sump at first 'causeI thought it was complicated and I was intimidated by the notion...but I've come to find out it would have actually made things EASIER for me. You can put your equipment in there and make the main tank that much less cluttered, plus you can do water changes and additions, tests, etc, without having to open up the top. You can have a sump without holes drilled in your tank (which I'm working on now) but it's just not an ideal way to go, and drilling holes in a tank you've already bought or set up is very much a hassle.

Anyway, I don't mean to overwhelm you with all this, which is probably what I'm doing...I'd suggest following Tony's suggestion, and looking up that book. Another good site for advice and reviews of equipment is About Saltwater Aquariums:


If you go slow, at a pace that's comfortable to you, I think you'll do just fine! Much of this stuff looks complicated on the surface, but is really dead simple when you get into it. Really. Honest. :wink:

Don't worry too much, it can be as simple or as hard as you make it. It is a big benifit to have experience but a lot of reading and preperation can make up for a lack of experience. Just make sure you read the equiptment list on this site and start checking out all the old posts. Once you've got the basic idea, you can start asking more specific questions. Remember, no question is a dumb one, so ask away. You could start with some easier fish like clowns or something but if you plan on getting an octo in the near future, it would be best to leave them out. Sea Stars and urchins are just as good indicators of how good you are taking care of the tank, plus they won't end up as snacks later. It can also be as cheap or as expensive as you want to make it. You can test your water with a "computer" or with a couple $10 test kits... you can buy an expensive water purification unit or you can buy the water from the pet store or Culligan for $.35 a gallon. As long as you don't jump into it with lack of knowledge you'll do great. The people that get into trouble are the ones that buy an octo from the store and then try to learn how to take care of it.
Oh...hehe...you asked about which inverts...forgot to mention that.

I've had good experience with various brittle stars, but watch out for the common green brittle star. They are apparently capable of catching and devouring fish. That might not be a problem in a cephtank, but who knows? Maybe it would eat other inverts too.

Mespilia globulus urchins (blue tuxedo urchins) are my urchin of choice. They're gorgeous, and have short, not-terribly-prickly spines, unlike Diadema. I had a pencil urchin, but I don't recommend those...he knocked everything over that he could, and broke pieces off my live rock (some species burrow into rock.)

Sand-sifting stars stir sand up regularly, which helps keep it looking clean.

Fromia sp. stars are pretty and are apparently hardy and harmless. Many traditional (non-brittle) stars will eat lots of things you might not want them to. The other commonly traded "safe" star, Linckia, I have heard are difficult to keep alive.

Sea cucumbers are questionable. They have some very odd habits. Cukes produce and concentrate toxins in their bodies, and under stress or upon death, these are released into the tank. This can kill ALL vertebrates present. Some species are worse than others. There are some suggestions that they won't kill other invertebrates. However, one defense mechanism involves expelling sticky intestine-like digestive organs from their mouths--were an octopus to be on the receiving end of this, it's possible it could be fatal.

Hey welcome to Tonmo

Being a fairly new member myself I had the same delema when it came to seting up my 1st saltwater aquarium. I have had great sucsess with the folowing combination. 1st rule is tank size the larger the better, get the biggest tank you can afford. The larger the tank the more stable the enviroment, the easyer it is to keep. 2nd rule is remove all nitrates and amonia from the water. I do this in three stages 1st the water is passed through a protein skimmer (foam fractionator) this is a coloum of water with lots of tiny bubbles that dissolved organic waste (decomposing food, urine, ect) and forms a stable foam that can be removed from the water via colection cups. Then the water passes through a sump containing bio balls. These are plastic balls that increase the surface area alowing the nitrifying bacteria to grow.
Third step is the water is then returned to the aquarium via two holes in the bottom of the tank through an under gravel filter again alowing the benifical bactera to grow and prosper. I also use mechanical filtration in the form of a Ocean clear canaster filter wich removes the largest particales and chemical filtration by the use of activated carbon in both the sump and the Ocean clear filter.
With this set up I can go 2 weeks and do a 25% water change and gravel vancumme and my Nitrate levels are never detectable same with ammonia. You can set up a tank with far less equptment but you will have to do water changes far more often.
As far as salt water is concernd if you live very near an ocean you can use that providing you get it checked for poluteants (heavy metals). I live right on the beach so geting the water is very easy for me. If not you can buy the salts and use pure water (reverse osmosis or distilled) will work the biggest killer of pet cephs is heavy metals in the water like copper or lead. Also dont use tap water beacuse they usualy contain chlorine or flouride also very posionus to fish.
That should give you an idea of what to expect to need to purchase plus of course things like heaters (2 watts per gallon) lights (octos would rather have none) Gravel ( crushed coral) Decorations (planting pots, rocks made in to caves, shells, ect, avoid wood) a accurate thermometer, test kits, the list goes on and on.
To cycle the tank I used 13 "evil" crabs and two bristle stars they made just enough waste to help the bacteria along. I also placed 3 small shrimp (1 inch) in the gravel to get some deacy and used a little used gravel from my local fish store. All and all it was a very sucsessfull start up.
I found the reef keepers network (http://mars.reefkeepers.net/USHomePage/default_us.html) to have some very good info, just ignore the lighting parts as octos dont like light. Of course posting a question is a great idea two. Might take a day or two but you will get an answer. If you have anymore questions dont hesitate to ask there are no stupid questions just dumb answers.
Warning Octopus are highly addictive and very cute! I dont recomend starting a tank unless you are willing to give up all social interaction with other humans and draining your bank account to buy the next larger tank or neat goodie to make your pet happy. I love myne and is a much better pet than any cat, but that is just my bias.

Pacific Blue 8)

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