okay, here's the situation...
I bought 2 mollies and 2 CAE on the same day from LFS. I bought them 2 days ago (11-Apr, 6PM). I use them to cycle my tank which is my initial plan. Then today (13-Apr, 6:30PM) I found so many fries in my tank. As everyone say, mollies are livebearer while CAE are egg-layers. So, is it possible for CAE to lay eggs in tank and hatch in 2 days? Or make more sense if the mollies I bought is pregnant and now they deliver fry today?