It is hard to sex the fish, especially from far way, your best bet is to take pictures like the ones below from sandstone's posts and it would probably be helpful to catelog them like he did.
Males tend to have a broader head and appear to have cheeks at which point the head runs straight back to the body.
Females have smaller, more curvy heads that appear to be curved all the way back to the fins. Females also tend to be smaller and fatter around the midsection.
Males also have odontodes (whiskers), that can be seen on the picture of the male (15), above, and illustrated on the picture below.
Hope this helps. If you still want second opinions try posting pics like sandstone's and I'm sure people will be willing to help.