I have four female Dalmation mollies in a 3 foot tank with one male Dalmation, two Bristlenose catfish, and one Khuli loach. The male spends all his time flaring his top fin and mating with any of the females that will let him near her, non stop. In fact, when I put him in my 4 foot tank, he'll try to mate with anything in there too like my Bala Sharks, which take great offence.
Originally, I only had one female and one male in the tank, but he was harassing her so much I felt bad, and added another three females in.
The very same day (three days ago) that I added the females in, one gave birth. Now I think it aborted a very heavy pregnancy, as most were dead straight away but some lived.
Now, the male is still in with the females. I haven't noticed any of the fish eat any babies, and they have this plastic grass type stuff they hide in (unfortunately the Khuli loach hides in there too, but haven't noticed him bothering with the babies).
a) remove the male, 100%,
b) just let them spawn properly once they are settled and see how things go, or
c) put any pregnant females in breeding boxes.
I have this clear breeding box where the babies can drop through, but I have heard if I put a female in too early, they stress and abort, and I wouldn't have a clue when the babies are due. I have heard of the flat bottom thing when they are ready to pop but yet to see it. The breeding box seems ridiculously small for the fish, it'd only be four times her length max. No wonder they would stress it.
I guess I'm hoping none of the fish in the tank will eat the babies and they'll just grow, but I could be very wrong!