if its white and milky, definitely a bacteria bloom
completely harmless and best option is to wait it out (will take about a week IIRC)
I honestly LOVE bacteria blooms...you see your tank and it bothers you and it bothers you and it bothers you...and just when youre about to give up and do "something"
BAM! crystal clear water! and you feel LIKE A BAUS!
Fraternity, Inc. #33