Sorry for your loss, that's never fun to find that. Are you sure it was the male? I've had a few of my females who were first-time moms kill their entire litters. I've never had a male do it, even if I foster babies he didn't father. I'd look more to the female than the male, especially if she's a first-time mom. If not, then maybe try it one more time with that male & if it happens again, he'd be the next meal if it were me. I know lack of water can cause them to become cannibalistic, if they're dehydrated. Not saying that was the case, just something to consider maybe. Good luck & again, sorry that happened to you.