You can identify BN plecos by their bristles. Male BN plecos have a lot of bristles. While females have just a little "mustache" or no bristles at all. At 1", that's too small to sex them. I think you can sex them at around 3" inches or so
My female albino BN has bristles like a mustache, but I was looking for a pair of starlight plecos (they're around 1"). I was wondering if there was another way to tell other than the bristles that can be determined at a younger age. Thanks!
Until the fish matures a bit, I do not know of any other way to sex the Bristle Nose Plecos. I have a female that is 4 or 5 years old now and I bought her from one of our members here. I was hoping for a male, but I couldn't be happier to be honest. The female is so tiny and feisty. I love her! She has very few and short bristles and is about 4" at the most.