Sexing Argentea?

[aclockworkorange]

My "Vieja" argentea (yes I'm aware of the genus change but this is the name everyone knows) are nice and settled into their 90 gallon growout. I have 6 at about 2".
I am really enjoying them so far... they are not shy at all and come right up to the glass and beg for food already.

Just a couple pics for fun...

I know they are essentially monomorphic gender-wise, especially when younger (males are bigger than females when mature, yes?), but does anyone have any techniques they've found to sex them?
And what size should I be looking at for them to pair up?

Thanks.

 

[aclockworkorange]

I've seen this as well...

 

[aclockworkorange]

Nobody?

 

[aclockworkorange]

Last bump.

 

[Chrisplosion]

I think it would be impossible to sex them at that size.

 

[aclockworkorange]

Yes, I assumed that, wanting to gleam some knowledge from someone who has actualy grown them out and gotten a pair. Also, I asked what size would they show signs of pairing up?

 

[Modest_Man]

Female-

Male-

Note the difference in spotting. Females will be smaller and rounder. Fins on females won't be as impressive as males. I could never get them "bonded" but I introduced the female when they were both adults already. Male just wanted to kill her.

 

[aclockworkorange]

I hear it's hard to get them bonded no matter what. Ive got my work cut out for me!

 

[Chrisplosion]

I hear it's hard to get them bonded no matter what. Ive got my work cut out for me!

Argentea or Vieja in general

 

[aclockworkorange]

All vieja, but especially argentea.