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Idea for a new tank...

Oct 13, 2005
I recently bought a 40 gallon tank from my uncle for very cheap. It came with a power filter, thermometers, test kits, you name it, it came with it. I was setting it up, putting water in, salt, ect., and I got to thinking...what should I out in this tank...the first thing that came to mind was an octopus. Would a 40 gallon be a suitable sized tank for a bimac? If not, I can get my hands on one of the infamous "Bali octopus", which I assume is an O. bocki, but I will not buy it unless I am sure of the ID. I have always wanted an octopus, as many of you know from my former posts, and now I think I cna actually do it. I have a bait shop nearby which I am sure sells crayfish, shrimp, and fiddler crabs for very cheap. I also have access to all the live rock I want for prices unimaginable. My mom is going right now to pick me up some very fine grain sand. I have a heater, but I doubt I will need it since summer is coming up. Do you guys think this set up sounds ok?

Brock Fluharty
FIrst thing you have to think about: Has this tank ever had copper treatement? That could be fatal to an octopus. Inverts are very sensitive to copper.

You may be planning this already, but you have to cycle your tank before you can put in an octopus. This will also give you time to grow some amphipods and get the tank fully ready.

Don't forget the protein skimmer - and have you read over our Ceph Care articles (such as the Equipment List and the Checklist) - lots of good info there on setting up to keep an octopus.

Seems like you're well set up for food and have good access to what you need. With a 40 gallon tank, you should look for an octo on the small side.

I know all about cycling, and sorry, I forgot to mention the protein skimmer. I do not have one yet, but I will probably get one rated or a 100 gallon tank or so. I have set up over 10 tanks, so I know the basics. This tank has never had copper in it, but I will double check with my uncle on that one. Also, I have heard that copper will stain the sealants. If so, the sealants are white, but I will still check. Are you suggesting something esides a bimac? Do you think this because it would be too big, or the bioload would be too big? If it's the bioload, that could easily be reprimanded by large, weekly water changes. How big do bimacs get from tentacle to tentacle? Like I said, I have easy, and dirt cheap access to a "Bali Octopus", which is also an option, but the downside is that most dwarfs are nocturnal, and not very interactive, and have a short lifespan. I was also thinking of breeding, so 2 bimacs in a 40 gallon is a definate no-no. I know the problems with cannibalism, but I simply cannot have a pet without breeding it. I think that animals are supposed to breed, and I try to make my animals habitats as natural as possible. Are O. bocki small egg species, or large egg? Are the babies easy to raise? Do you think I could even keep 2 O. bocki in a 40 gallon? If that is what these are. I could probably get a picture, and post it in the ID forum, but i'm no sure, since it is a wholesaler.

Brock Fluharty

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