A long time ago, when I photographed these males I did not know that they were both males. I was still hoping that they might be a male and a female and become a breeding pair. However, as they both continued to grow older, bigger and more mature, it eventually became clear that both of them turned out to be males. Then I bought another juvenile, hoping for a female. The juvenile also grew up, but unfortunately it also turned out to be a male. I moved on, breeding other species and never got a female Hypancistrus zebra. I no longer have the males. Maybe someday I'll try a new group of Hypancistrus zebra and maybe then I'll have better luck getting a breeding pair?