When can you tell sex of molly fries?

  1. K

    Kendra New Member Member

    hi everyone,
    I'm just wondering when can you tell sex of molly fries? My fries are just a bit over 5 weeks now and I have noticed one of them constantly follow the female adults and show mating posture. Does that mean he will be a boy later on? his anal fin is becoming more triangular than the other fries. All the fries are about 1.8cm-2cm now. I dont want them to interbreed so I want to take out the male but I'm not 100% sure he is a male yet. If I leave him in the tank for another 6 weeks (cause I'm going away soon), is there a possibility that they can reproduce? or is he too young to do that? thank you

  2. N

    Nieveso New Member Member

    not neccecarily my guppy fry atm are one month and 4 days old but i have to squint to see colour keep a close eye on their anal fins if its a boy they will soon become pointed then eventually turn into a gonopodium by the sounds of that one yes he is a boy but they cant reproduce till 3 months old so you have nothing to worry about. But why dont you want them to interbreed if you do that for a while and sell the throwbacks and then eventually sell the good ones you could make some decent cash$$$ :D ???