That's what makes life interesting with bolivians
The only sure fire way to tell is by the vent, other things are just indicators. Females have round bellies, males are flat towards the tail - but so are undernourished females, a common thing in shop tanks. Males have fin extensions at the front of the dorsal fin and the edges of the tail fin - but juvenile males haven't grown them yet, and shops usually have juvies for sale.
You've not had your long yet. Let them settle and grow a bit, it should be easier to tell then. If they breed, you'll know for sure
The only sure fire way to tell is by the vent, other things are just indicators. Females have round bellies, males are flat towards the tail - but so are undernourished females, a common thing in shop tanks. Males have fin extensions at the front of the dorsal fin and the edges of the tail fin - but juvenile males haven't grown them yet, and shops usually have juvies for sale.
You've not had your long yet. Let them settle and grow a bit, it should be easier to tell then. If they breed, you'll know for sure