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First time octo tank - is my plan good?


O. vulgaris
Jun 12, 2004
Hi everybody,

I am new to octopuses but not that new to aquariums. I have a 120g freshwater and a 10g freshwater with plans for another 15g fw, and I have learned a lot about SW by helping my girlfriend set up a 15g sw for herself.

I decided that I want to get a sw tank to house my gf's yellow watchman goby while she is out of the country this summer, and to hold a clownfish for another friend of mine. After the summer when I free this tank up, I plan to get my octo!

The tank I think I want is a 60g cube. I plan to put a whisper330 (dual outtake, very large biowheel-using hang on tank filter) and a very decent hang-on-side protein skimmer. I'm choosing this over external canister because I want skimming, and I want more aeration. I know a sump is 'the way', but frankly I am not worried about nitrates (and don't understand how a sump reduces this anyway), and more importantly I AM concerned about this loud noise!! I plan to have this tank directly against my bed (my 120g is 1 foot from the foot of my bed) so I couldn't put up with rushing water all night. I'll be lucky if I can sleep with an octopus a foot away from my head! :smile: I feel that with a lot of tape and thinking I can seal up the tank, despite having large holes for the hang-on-side filter/skimmer. I also am going to be using probably a 150 or 200 watt heater. This is the only reason I think not having a sump is bad, because I'm afraid the heater will be broken or abused by the octo...

As for the insides, I am planning on putting down about 1 inch or less of crushed coral as a buffer, followed by about 2 inches of live sand. On top of this I guess I am thinking about 60 pounds of LR. I have heard that octopuses can throw and move rocks around, and that you should anchor or glue them together to avoid this. It doesn't seem realistic to glue LR together, so should I just try to get VERY large pieces? Or is this a fairly overparanoid worry in the first place? Also I'm thinking about putting some easy corals in the tank, ones that don't require special lighting or additives etc. I read that bimacs are not 'reef safe'.. but I don't see anywhere /why/ (unless its because they move the corals around).

Another question is if the octopus were to get out, could it actually bite and injure someone? Also could I keep a large star with it? Are there any tankmates that really have a chance of NOT getting eaten?

Sorry for the deluge of questions but I'm really curious and info seems hard to come by!!!

Thanks for your replies,
Hi Robert,

This should be interesting - an octopus a foot from your head while you sleep! He'll probably watch you at night - but don't worry, they're very friendly!

Also, people pay money to buy little machines that imitate the sound of running water to help you sleep well - maybe an overflow and sump wouldn't be so bad!

You don't say what species you're getting. If you're getting a bimac, you might not need that heater. The challenge is ususally to keep the tank cool enough, since the recommended temperatues are between about 72-65 degrees F.

People do sometimes get bitten by their bimacs (and other species), usually when the octo is young and being hand fed but this usually happens only once. You can see a video of this and some pics under Journals and Photos (The Agent Bites, for instance). Octopuses don't get out and then climb on someone and bite them!

Octopuses can move and topple very large pieces of live rock (I know from experience!). You need to build a sturdy live rock contruction with large and small dens built in. Yes, you can glue live rock together.

At least this is a start on answering your questions!

Thanks for the reply!

Yes I am planning to get a bimac, I did not realize that they required such cool temperatures. I had read that they required 72-76 but I guess this is not accurate. I am planning to keep newts and I know they need cooler water, and I have read about making a contraption that can drip water from ice cubes into the tank... is keeping at about 70 bad (other than a shorter/more active lifespan), and also is it bad to allow the temperature to fluxuate over the course of a day (if I went the no heater/cooler route)

I don't understand how I would glue the rock together? Obviously I would use aquarium sealant, but I couldn't exactly take the rock out of the water and glue it and let it dry.. it would kill the rock. And I couldn't glue it while it was in the water? Maybe you can shed some light on this

Thanks a lot, I'll check out the videos!


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