I'm still a bit occupied by this issue. Could it be an idea to add a field to the breeding stats where it says if the fry was handraised or left with the father?
In addition to the water parameters, maybe that could give us some material to work out a statistics where this, in my opinion, important issue regarding enviroment can be included?
A field stating how many snubnoses out of the total would have to be included as well of course
On an additional note on this subject, I added a "bumper rail" system in my caves and the one spawn of 13 that I've had since it's addition had 0 snubnosed fry.
I glued two marbles to the back end of the cave. That left space around the marbles for the fry to go without being smushed by dad. It seemed to work well, although the males didn't prefer those caves, obviously . I've since been using an assortment of caves with more rounded backs, also with good luck.