It is best to keep him in there, but in order to know for sure, you'll have to just let Nature do her thing for a few times. IBC Grand Champion (and a mentor to me) Karen Mac Auley always advises us young breeders not to interfere too much with nature. In following her advice, I've been quite happy with what has worked out for me.
There are some who think that egg-eating fish can pass this poor parenting instinct on to their offspring, so if your sentiments about breeding are still what they were in your other thread (that breeding for show is damaging the species), then you should probably not try to artificially raise the eggs of an egg-eating male and get a different male if he does not work out.
(Many times, the first time or two a male breeds can result in infertile eggs due to his lack of knowledge on how to wrap the girl. In these cases, he always eats the unfertilized eggs to prevent egg-eating fungus from getting into his nest. Eating eggs for the first time or two does NOT mean that he is necessarily a malicious egg-eater.)
Again, the only way to know for sure is to give him two or three chances in which you don't meddle and don't stress him out. Otherwise, you won't know for sure. I do this before putting my breeders permanently on the bench.
I am just so nervous of all the babies being slaughtered by the jaws of their own father. I watched one of our mares nearly stomp her foal to death when I was 10, it was her first foal and she had no idea what she was doing, the foal frightened her and she grabbed it and threw it against the stall. Needless to say we ended up hand raising her and the mare did fine on her second foal and was great but she just turned on her first. Not common but it happens and horses die if not properly watched. From what I hear egg eaters are more common than they use to be in all the threads about them and it concerns me what percentage are they as far as common goes? 50% 40% 30% 20% unknown?
And I never said that show breeders are destroying the breed but you have to admit all breeders who show won't be ethical. People will do horrid things when prizes are involved. Having grown up on one of the top Arabian Halter horse breeding farms I know it myself. Sometimes young horses at the bigger barns were forced into serious pain to become better flashier performance horses, the inside of their eyes were tattooed so you couldn't see when they were scared and showed the whites of their eyes, horses tails were bleached or dyed, and some people even did plastic surgery or just went the other direction and killed their competitors horses or beat them (happened to one of our horses). Even in the mouse world some of the top breeders have stated on average their bucks live 8-9 months, just "long enough to win shows and produce offspring then die of cancer and other ailments that can be weeded out with great breeding.' But it wasn't about the mice it was about winning, if the mice die young it means you have more room to produce more champions. This is the view of breeding I detest.I still help breed horses for shows and some day mice but you can bet my animals will be sound of mind and good in health so they are not just short lived models, they can be pets and healthy as well.
I can see how traumatizing your examples would be to any horse, but I wasn't trying to pick on you.
I was simply explaining that parenting in fish is an instinctual behavior. Egg-eating fathers can produce egg-eating offspring, or so they say. So the solution to keeping egg-eating behavior as far away from your line as possible is to not have egg-eating parents as part of the equation.
However, it takes some time to determine whether a fish is an egg-eater or not. As cruel as it sounds, if things are not allowed to progress naturally, then you'll never know.
A father eating his eggs or newly hatched fry, by the way, is a much more humane method of culling fish (by letting it occur as it may naturally, ie. the weaker swimmers are eaten by bigger fish) than having to raise the babies and cull them in other ways when they get older.
I personally have only had to cull 3 fish for health/deformity issues. I am now doing water changes on about 80 jars on top of my breeders' living arrangements, and it will take me a great deal of time to rehome babies of this amount. However, I just do not have the heart to cull perfectly healthy fish if I have the time to give them proper care.