need to noe wad needed...please help

Aug 11, 2004
HEY folks im goin to try my very first sailt water tank .i chose an octo 4 .i dun noe wad i need (wad should be the tank size) and the minimum requirements for the tank :x so if the experts are out there please help me.and wad are the small octopus i can find in the aquariums.
:welcome: to TONMO!

Look through Colin's equipment list in the Octopus Care section; the minimum tank size for an Octopus bimaculoides is 55 gallons. O. bimaculoides stays relatively small, but we've had some giant ones. The smallest octo you can easily get would be Octopus joubini, or more likely Octopus mercatis, but they don't live long (6 months is their full lifespan) and are sold as adults with only a week or a month or so left to live.
Hey you should do some research! Nancy and Colin run a great site. You should look at the ceph care on this site. This site is just LOADED with info. just take some time to look at it all.... it might take a while and its tempting to just jump right in and start but investigating is worth it you shoul learn all you can.
Good luck, Evan
Don't get a blue ring period. They'll kill you and if they're in a tank less than one gallon they have all the more reason to escape.

What do you mean by a normal filter?
Anyone even considering keeping an octo needs to go to our Ceph Care page and read the articles. You'll find lots of good information and will have a better idea about what ceph keeping entails. Read the Equipment List and the Checklist for starters.

Remember, you have to have or develop salt water aquarium skills, and have lots to learn before considering any octopus - this requires a lot of your time, dedication and some cost.

Also, start with the needs of the octopus - tiny tanks won't work!


hey mu mum gave me a budget of $200 coz its my bday today14 augustso happy :rainbow: anyway i bouth a 29 gal tank alredy so can i keep a small octo inside?and i m using the normal hang on filter can it be used?and i dun want to use the protein skimmer ...its too expensive...
anyway thanx 4 ur support haha :biggrin2:
Hello aaron,
I am sorry if I have to probably "pop" your bubble here but please consider what I have to say:

I was once like you. I've learned that you can keep an octopus in a home aquarium and I was fascinated by the thought. So I asked around, and began making a list of stuff that would be needed.
Unfortunately that is where the though part kicks in:
An octopus is a saltwater creature, and saltwater creatures are MUCH more sensitive to any fluctuations in water quality than freshwater fish. so water quality has to be your absolute top priority. Also, being a creature that lives in the open sea, it NEEDS some room. so the bigger the species, the bigger the tank has to be.
Please take note that you have to constantly monitor the water quality, temperature, salinity and so on which also produces costs and also you have to know what you are doing there. I don't mean to offend you, I just want to say that maintaining a saltwater tank is quite a bit of work and requires much more dedication than keeping a freshwater one.
Also you said you don't want to use the skimmer because it is expensive.
Unfortunately, if you think you can't afford it, you probably should consider if this is really the right hobby for you. Please note that setting up an octo tank IS expensive. There is no way to get around this, absolutely no way.

Here is a short summary of what you must consider when planning to buy a octo tank:

Size: It HAS to be big, the octo needs room and also the more water you have in the tank, the more stable is the quality. Also you ahve to make the whole thing escape proof

Filter: octopusses produce a LOT of waste, so the filter has to be overspec. e.g. for a 50gal tank (probably the minimum size) you need a filter for at least a 70-90 gal tank, if not even more. also the standard hang-on filters do not cut it in most cases unless you pay enough money for them.

Skimmer: same here. Absolutely necsessary. The skimmer gets out the stuff that the filter doesn't. And for an octo tank this thing is necessary, no way around this one.

Water: Here comes the critical part. octos are very sensitive to water quality so you have to constantly monitor it. Note that you may not use tap water by any means. also you have to do regular water changes, meaning you have to constantly mix fresh salt water , monitor it's salinity, oxygen level, temperature, nitrit, nitrate, copper (this is DEADLY for an octo!), ammonium and so on.

food: an octo is quite the eating machine. Scallops, shrimp, crabs, mussels... this also can get quite expensive so be sure to a) have enough money for this and b) have a source of food.

I could go on like this for some time, but you probably see where this leads.
I don't want to offend you in any way, I just want you to realize that this is anything but an inexpensive hobby... quite the opposite actually.
I've learned this lesson myself, and I urge you to reconsider if this all (and more) is REALLY the thing you want to do.
yeah, a suitable investment would be around 500-1000 a break in time of three months prior to octo may want to rethink your tank strategy!
Keep us informed!
Possibly the bottom of the line protein skimmer is a Prizm Skimmer. It's difficult to adjust, but will do the job. The box recommends it for up to 100 gallon aquariums, but it really depends on the bio load in the tank. I'd say it's ok for less than 50 gallons. perfect for a 29 gal tank.

I've seen it for 75 up to 90 dollars for sale.

I have one of these on my tank and we use them at the fish store I work at.

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