Thank you all, –
Regarding determining sex … I am curios regarding the photoes of the young parvulus fry. It is quite obvious that these fry has small red dots in the dorsal and pelvic fin – but if these show up in both males and females ? I wonder.
You can see what I mean at the photo earlier in this thread.
Another fun image I took today – of two very very young P. nagyi ‘cherating’ (from my 60 liter with 12 fish) (they obviously spawned :))
At least here its kind of obviouos that quarelling about space starts quite early