If you do use the sponge filter be sure you attach it to the tank so that it does go to the bottom and catch little fry under it. You can easily attach the filter with a clothspin.
I have a livebearer which I believe it a platy. I saw the male and female last night mating. I have a breeder container in the tank with some baby's from last month which I saved.
I was wondering how you can be sure when to put the pregnant mother fish in the breeder to save the babies. Some...