Yep, it must be 2 males. With both my female cons, they showed orange on their bellies almost immediately after I bought them and they were both about 1" to 1.5" then. And the orange is there probably 95% of the time.
One time my pink female went totally pink again but it only lasted a couple of days and then she started showing orange again.
When I had the 2 females in the same tank, the pink one, which is bigger than the stripped one, chased the other nearly all the time. At the time, I thought they were argueing over the stripped male I had in there with them. But, the male died for some unknown reason and the 2 females kept at it. They are no longer in the same tank, but it was interesting to watch them.
Let us know how it goes, ok? 8)