Thanks for the responses, that helps a lot!
I drink regular water during the day, but at home, since I have mostly given up diet soda (except for occasionally out at restaurants or something), but I miss the 'fizz' aspect, so I drink carbonated water.
I don't tend to retain water at any other time other than TOM, when I tend to gain a pound or so (and then drop it once it's over). I didn't realize drinking more than my usual amount of water would perhaps help that.
And Alana, thanks! It's always nice to put faces to names, and I figured it was time for a new one of me.