Depends on how you look at it.
Had the female of allowed him to guard the eggs and raise the fry with her I highly doubt there would be any problems with him eating the fry.
The bigger issue is regarding the pre and post spawn aggression which both fish would display. From what I read and understand this is common but was not something I enjoyed watching.
A fair bit of damage to both fish would take place. Swollen mouths, torn fins, battle wounds on the body of the fish. All of which heals in time but could cause problems. In the wild fish would have much more room to separate and not be under so much aggression.
Since I always wanted to keep the male I got rid of my female.