I scoured the net and as i can observed they are both male basing on its tail (maybe im wrong) and so decided not to put sand,but they tried to mate now ive seen crushed egg shells so possibly I have a couple??? could this be an empty shell? do i have a couple then?
If there are eggs in the tank you definitely have at least one female. Males do not lay eggs . They will lay eggs regardless of weather or not they are a pair. Females produce eggs even without a male present , they just wont be fertile.