Both male and female have the tubes. The females is more crayon tip shaped, and males more pencil tip. Is she claiming a spot in the tank? Make sure she has a nice flat surface to lay eggs on. If you have sand in your tank she can go on for days moving the sand, which falls back down. Give her a nice rock of pot or something. When the vent comes out a whole lot, eggs are coming. Turn off the lights and the mating will happen faster in some cases. Good luck!