Just guessing: Similar to the close relative C. lorteti, who was spawned several times. I'd keep the pH down to 6, this may resemble their natural habitat best. Temperature could also be varied, in case it is some kind of trigger.
On the lorteti the males swam around the females with erected keels and puffed up during courtship. They could appreciate some java moss to lay the eggs in.
I've had puffing and I've got lots of java moss, but no eggs, ever.
Would be great if your irrubescos would breed. Good luck!
my male lunges at my female - and she always gets out of the way, but it doesnt seem as though he is trying to kill her or anything, he has the red line on his belly, so i expect its something to do with sexual frustration maybe, she is a bit gorgeous so he surely would want her!
My male gets red on his belly and back
And I also think that the salivator pair is in the mood for love ;P
The male is showing many signs of courtship!
I think it`s good that I let them be alone in the 240l.
The male is sometimes red on his back and they are getting on very well 
Some call it a product of a mis-spent youth, I call it Rock n Roll ! 
