is there any way to sex a 3 month old bimac? i am getting two and i would like to eventually try to rear them? any experiences any one can share? thans

I have heard from people who've kept many bimacs that they consider them almost impossible to sex. I wasn't able to - when my bimac finally produced eggs, I realized she was a female. :smile:

Are you keeping them in separate tanks? Experiences with keeping two bimacs together haven't been good - one dominates and the other won't come out - or, one may kill the other.

Nancy

i plan on putting a divider in my 125 gallon tank. how do you know when to put them together for egg laying

I read somewhere that one of themale's arms (I think third to the right...) is pretty bare of suction cups, but has a few larger ones at the base, and all suction cups are the same size. Not sure how reliable this is...

I read somewhere that one of themale's arms (I think third to the right...) is pretty bare of suction cups, but has a few larger ones at the base, and all suction cups are the same size. Not sure how reliable this is...

In cephs in general, males usually have a modified arm, but which arm it is depends on the species, and it's often very subtle and hard to see. In bimacs, it seems to be a minor enough difference that it can't really be seen in a live animal under normal pet-keeping conditions. In some species, it's much more pronounced, and sometimes there are other things to look for... in GPOs, for example, the males have some extra-large suckers that are pretty easy to see. I'm not sure when these sexual characteristics develop, either-- before the male reaches sexual maturity, they may not be present, or may be much harder to see.