Live well drain

[PeterM]

Here is a question with winter coming up. My live well can only drain via a pump. There is no way to drain it into the bilge. It fills up when it rains. Should I cut in a drain hole with a screw stopper so that any rain water goes into the bilge and then out stern plug? I am concerned the live well might fill and freeze over the winter, even with a boat cover....what do you think? Or do I just leave some antifreeze and a sponge in the well?