DB-100 did the same thing to my water. I have bottom aerators running as well as a floating fountain and with all the agitation it made the top of my pond white and foamy for a few days. The water actually looked and kind of felt "thick" when you stirred it. I would imagine it probably does stress the fish out a bit when you put a large amount in the water at a time. But like I said I have no fish in my pond yet so I'm willing to try the DB200.
