Quoting Kayleigh-louise Moran:" How old should a baby be before you can take it to baby swimming lessons?I've seen some that start from just a few weeks but wasn't thinking of going till mines at 3 months?"
I wish we had a place around here, but you can take them anytime. I taught baby swim lessons over the summer for a few years. I've actually seen a 6month old SWIM! it's natural to them they will roll over when they need to breath and float!
But if you wait until 3 months I think your good.