How Long To Keep Fry With Mother?

[melknee]

My dempseys hatched fry 12 days ago and they've thinned out significantly, from about 200 to less than 50 , I'm afraid I waited too long to separate them from their parents and I'm attempting to catch them and put them in their own tank because I suspect they might be getting eaten by the dad. I still want to know when the best time to separate the fry from the parents is because I believe the parents laid more eggs. I'm inclined to do it when I first see them but I read that cichlids were good parents so I'm not sure. Thanks in advance for the advice