Mopping Woes - Advice Needed

Hi all! I need some help here. So I mop my hard floors at least twice a week. I go over them multiple times and I have one of those spin mop buckets with the separate water chambers and use just a little bit of non-sticky floor cleaner. The problem I'm having is that even after sometimes 7 (!!!) passes, the water is still dirty. Obviously it gets better and better with each pass, but I'm really frustrated lol. Any tips for me?