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Multiple bimacs in 1 tank?


Oct 16, 2003
Is it possible to house 2 bimacs in 1 tank? The tank is a 150 gallon. I have heard conflicting info on this 1 LFS told me yes it is possible and I have done so before, another said absolutly not 2 will fight to the death.
Another question is it possible to house a lion fish or a sting ray in the tank with a bimac? Once again I have heard conflicting info and the same results from the 2 LFS's.
Hi and welcome to TONMO.com,

I have yet to hear of anyone successfully keeping two bimacs in one tank. I do know of instances where this was tried and one did kill the other.

We get this type of question often, and the answer is, no, you can't house a lion fish or stingray with your bimac. I suppose, since you have a big tank, you want to have some other things in it. You can look back over past postings and see what our members have tried. I have a pencil urchin, a couple of snails, and a couple of blue-leg hermit crabs with mine, and some creatures from the live rock like a limpet. You can have a very beautiful tank this way.

A bimac can grow fairly large and would enjoy your 150 gallon tank. Take a look at my pics of Ollie on Journals and Photos - and he does like to zoom around the tank, too.

Hope this helps,
The sad part about the info I recieved is that the LFS that told me I could keep 2 bimacs and have a lion fish or a sting ray together is the much more reputable, knowledgable and stocks healthier animals than the one that told me I cant have 2 bimacs together or have 1 with a sting ray or lion fish.
Sometimes an LFS can be very good with fish, even salt water fish and invertebrates, but know nothing about octopuses. Unfortunately, this doesn't stop them from having opinions.

We have lots of info here on this website (have a look at the articles, especially Colin's Equipment List and my Checklist. Soon you'll know much more than the people at your LFS.

i actually kept an octo in the same tank with a large hermit and a bicolor angel, all three were about the same size, they got along for a couple of months until the hermit crab got ahold of the angel and ate it, then the octo ate the hermit, not to long after the octo found a way out and i found him on the floor, but it was very cool while it lasted
I have kept an octopus with wasabe and the cuttle before it. They didn't really care much for each other though wasabe was shocked the first time the octo came out.( Im beginning to suspect the octo killed the former.)

In fact, they seldom saw each other as the octo was nocturnal while the cuttle was diurnal.

I would suggest that you do not put 2 bimacs together regardless of what sex they are. They have a few month window to kill each other before they mate. You might want to search for the thread titled Tom and Jerry, you'll find out what happens with two bimacs together. :smile:

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