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Minimum Tank Size?


O. vulgaris
Aug 1, 2007
What octopus species could i keep in my 36 gallon bowfront? I was thinking aculeatus but i could be wrong. What about mercs? Could i keep a group or a pair of them in that size tank? Or would i be better off with bandensis?

Please help me make the right decision!


Staff member
Sep 4, 2006
Gainesville, GA
I would worry about movement space for an aculeatus but with some creative liverock work you might be able to provide more swimming space because of the bow front by creating a jetty with your LR. Water quality is also a concern if you have no attached sump.

You could easily have 3-5 mercs if you are willing to accept the idea that they are nocturnal and will not come out with lights on in the room. Red lights over the tank 24/7 worked very well for me for both mercs and my macropus). Mercs don't interact much and a smaller tank is likely to give better association. I had one female and two males that I raised in the 45 and they mated and produced viable young. That tank would easily have accomodated more.

For cuttle suggestions, hopefully Thales or Cuttlegirl will suggest and answer, the two I tried did not survive more than a month.

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