• 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.

First Octo Tank

Free Diver

Aug 20, 2005
Hey everyone,
I have decided to start to decided to start a bimac tank. After countless hours of research I think that a bimac will be the best species for me to keep. I plan on getting either a 30g or 37g and will have 10g fuge regardless. I know octos are messy eaters for having a HOB would be a good idea, yes? I will have 30 pounds LR, 2-3" deep sand bed. And a few pices of PVC couldn't hurt either. How many powerheads should i have in there. I have been reef keeping for 2 years and have always had a freshwater tank around. THere is another problem where do I get a bimac? I know of octopets and have read the posts on how some people love it and others hate it. Octopets is in Carlsbad Which is only an hour away from where I live but he hasen't had any luck with the last two generations. I always see octos when I free dive but i would feel bad taking one from the wild and the ones that I see are fully mature so it wouldn't live long. Does the plan sound good?

Hi Free Diver, :welcome:

That's too bad about Octopets, I'd would definitely want to deal with them, particularly in light of your SoCal location. Luckily you're on a site bristling with experienced octo-keepers, so you ought to be getting a lot of expert advice shortly from Nancy, Colin, Cthulhu77, et al.! Good luck!
Hi Free Diver and welcome to TONMO.com!

Jean is right, we are recommending a 50 gallon tank as a minimum for a bimac. If you've kept freshwater tanks, be sure you don't recycle one of these as an octo tank if any copper based medication has ever been used.

You're going to need a good skimmer, one powerhead and some sort of good filtration. A lot of us use a wet/dry filter and sump. For more information, read the Equipment List (link is on the Ceph Care page, just click on the Ceph Care button above).

People seem quite happy with Octopets. Have a look at the List of Our Octopuses (top of Journals and Photos forum) and you'll see that most of the bimacs come from there.

I'd go with a less deep sand bed - 1-2 inches - your bimac can dig right down to the bottom. Also, make sure it has room to swim and a sandy area in the front of the tank, so not more than 1 pound of liverock per gallon.

Thanks Nancy I have decided to go with a bigger tank and have 2 skimmers. I do know that copper kills based on my reef tank experiences. Will I need a fuge or will a wek dry do it? And for powerheads what powerheads are more octosafe than others? What model types are good and how many? Thanks for all the input.

Yep, what she said !!!
I like refugium/sumps, but I also have a glass drill, and have been known to go crazy with it...
as far as types of flow/powerheads, I have had really good luck with Rio's for my reef and ceph tanks... they are easy to cover, and hold up well for the $$$.

Glad you opted for the larger tank...it will pan out much better in the long run!

Hi bret, welcome to TONMO.com :)

good advice there, the bigger the tank the easier it will be
cthculhu what do you mean by covering the power heads? Should I cover them with mesh? And how much flow is too much? Should the flow be the same as a reef tank? Is there a gph to gallon ratio?

Thanks again
If you are getting a bimac, they are used to very heavy surges...so the bigger the better (as long as water isn't shooting out of your tank!) I would estimate a Rio 600 or two would be fine.
I like to use foam to cover my intakes...yeah, I know, it decreases the water flow, but an octo can't fit through foam !!!! If you can land an old Tetra airlift style filter (green plastic with black foam head), just take that foam and put it over the intake...viola !!!!
Ok I'm looking into a used reef tank. It is a 60g has 75 pounds of LR and a 3 inch sand bed and comes with a wet/dry that has a UV sterilizer, Osonizer(?) and room for skimmers. I'm so excited! It also comes with a 175 watt metal halide and two fuval 303 filters. All for $150!

yep, sell off the halides, and get rid of that much sand...about an inch or so is fine (less chance of tank crash due to anaerobic decay)...what a deal though !!!
Can hardly wait to see some pics (hint)

Im goin to Kauia in 2 days and will not have the tank untill I come back. I'll take some pics of octos when I got diving. Yeah aboot the halide I'm going to use it over my reef tank.

Thanks again

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