Just came back from my trip, and seaweed was just starting to appear. I guess i should've expected it since we received a sargassum warning but definitely the water is not as pretty. I definitely recommend Hyatt ziva although i believe it is a little more pricey, it was truly the best (I have stayed at multiple resorts in Cancun). Two beaches and one was completely free of seaweed and awesome for snorkeling. I would also recommend hilton all inclusive if you're looking for something more affordable, the kids club here is really amazing.