Golly?

[daydreamer4186]

Several months ago I got 2 female silver sailfin mollies. I already had a male fancy tail guppy in the tank when they were introduced. I also that the guppy was constantly chasing them around and getting quite "friendly" with them. Eventually both mollies each had fry. Fast forward to now...several months later...many of the fry have grown into good sized, healthy fish. All of the females loot like their mothers but the males look a little different. They have the same size and body shape as male mollies and are all silver but they are starting to get color on their tails. They have little bits of an aqua color and are starting to get a very thin line of black around the edge of their tails as well. Do you think that the guppy might be the father? Any thoughts on this in general?