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Alright. I have a tank.


Blue Ring
Aug 29, 2007
Hey everybody, I'm still looking forward to getting a pet octo of my own :smile:

My friend gave me his old aquarium, and it's pretty big. I'm not sure how many gallons, but it seems like it will be alot more than enough. Now i'm not sure where to start, what kind of water should i put it in, what kind of sand, any decorations? I know absolutely nothing at all about aquariums, so i'm not sure how to set it up properly to recieve the octo, though i know i will have to leave it a few months. What materials will i need to purchase? Thank you.

Also, a few off-topic questions:

What would be the good species of octos that are interactive? A decent-sized one, that lives for about 10 months, and that you can pick up or touch without it trying to kill you? :3

Also, is it possible to get one of these kinds of squids as a pet?

Getting a squid is going to be pretty difficult unless you go to some coastal area where you can find them. Someone actually posted pictures of one they caught in a bucket not long ago. BUT, they are just about impossible to keep in an aquarium.

You need to determine the size of the tank. Get a measuring tape and give us the width, height and depth meausurements and someone will be able to tell you how many gallons you have. You need at least a 50 gallon.

For an interactive species you probably want to go with a Bimac. The ones we have received from Saltwaterfish.com are also very interactive, or at least they are active during the day and don't hide too much.

You should read all of the care articles on this website. Click on the ARTICLES link under the big TONMO logo at the top of the screen. They will answer almost all of your husbandry questions. The most important thing you can do right now is BE PATIENT! Read, read, and read some more! Do as much research as you possibly can and make sure you're getting your information from reliable sources.

If you have a 50 gallon, you want filtration for about 150 gallons. Octos are VERY messy and will ruin the water really fast and you need sufficient filtration to keep the water from going bad too fast for you to handle.

First thing first though, set the tank up. Get water, live rock, and live sand in it, let it cycle, and then learn how to deal with the ammonia, nitrite, and nitrate cycle. If you have a local fish store that sells pre-mixed saltwater, that is probably the way to go for now. For live sand, you can really just look at what's available and pick whatever color you want. As long as it is actually sand, and not crushed coral, it should be fine. If you have a 50 gallon, you want at least 50lbs of live rock. Live rock is the main ingredient in your tanks filtration system, plus you just can't beat the natural look. Hope that sets you off in the right direction.

Other than that, welcome to TONMO!
Alright thanks Animal Mother, but exactly does 'Let the aquarium cycle' mean? I just leave the aquarium there for a few months? Also, when i recieve the octo, do i just dump it out of the bag and into the aquarium?
This should answer your cycle questions... Cycling a New Saltwater Aquarium Without Fish

You want to acclimate most every living creature you put into the tank slowly, over a couple of hours for an octopus, much less for something like Hermit crabs or snails. I usually do just dump hermits and snails in and I've never had any issues doing that, but it's not a good idea with most fish and you want to be real careful with an octopus.

You can use a bucket or some other container to put the octopus and the water it comes in, and run a drip-line (airline tubing you can find at the local fish store "LFS") to the bucket, slowly dripping water into the bucket from the tank. This lets the octopus adapt to the water in your tank without some immediate shock, since the water it comes in is going to be different from the water in the tank.

There are a lot of things about water chemistry you're going to have to learn to keep a saltwater tank. It's not as complicated as it may sound at first though.
cycle breakdown...

the goal it to build up colonies of bacteria that breakdown ammonia(very harmful) into nitrItes(just as harmful) into nitrAtes witch are less harmful but still need to be kept to aminimum with water changes.

fist you need bacteria that breaks down ammonia into nitrites. this bacteria will biuld in your filters if you provided it with ammonia to eat. one way to do this is to introduce a hardy fish. the better way to do this is put something already dead in the tank like shrimp. this is a good time to add live rock.

once that bacteria has established itself nitrites will show up in the tank. eventually a secondary colony of bacteria will form that eats the nitrites and converts them into nitrate.

no bacteria is going to eat the nitrates that build up so those will have to be kept down with regular water changes

cycling generally takes 1-2 months
water you will need to find a source of RO/DI water. some stores sell this or you can buy an RO unit to filter the water in your house. you cannot use regular tap water because it probably has loads of impurities including copper(lethal for octos)

you will also need a good aquarium salt (i use instant ocean) and a water testing kit. get the liquid kind if you can as these tend to be more accurate. get test for ammonia nitrate nitrite and pH. also get a hydrometer to test for specific gravity(amount of salt in the water)
get some netting to cover any areas were the octo could get into a filter or escape, get a gravel vack or something simaler to siphon water out for changes and a bucket or two.

you also will need to look into what filter system you want (protein skimmer is a must)

and keep reading up on aquariums as their is plenty i havent mentioned
Do you know what was in the old aquarium? You need to make sure that your friend did not treat the animals in the aquarium with any copper-based medicines. Copper is fatal to octopus. Also make sure not to clean the aquarium with any type of soap.

You need to find a good local fish store, they may be able to help with some of your questions. Are there any local aquarium societies near you? They can sometimes help with advice and second-hand equipment.

Lastly, if there is a public aquarium near you, see if you can volunteer in the husbandry department. You will get to help clean, feed and maintain their exhibits and learn about caring for salt water animals. Sometimes public aquariums have classes on how to set up salt water aquariums.

Good luck!
Cephalopods are some of the most difficult things to keep in an aquarium. I think it would be best for you to wait until you have some saltwater experience. You might be trying to paint the Mona Lisa on your first canvas.
I have a question. If i put a crab in my hand to go give it to an octopus, will it try to eat me? :I

EDIT: Also, if i buy an old aquarium (that used to be a vivarium) that's 88 gallons, will it matter if i add water and cycle it correctly? As in, would it matter that it used to house land animals?

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