Thanks for the suggestions. Is it safe to assume that every time you add alum there will be some flocking and all the alum will be bound up, even if there is no apparent clearing? If that's the case, could one add alum, providing there is no additional clay input, in increments to clear the water gradually? That's the way it looked like it was working when I did the 5g bucket test. I know you said it's best to clear it up and build up a positive charge in the water, but today I saw the first signs of Chara and when the sunlight hits that stuff, it goes crazy. I put a little herbicide on it in places to keep it from overgrowing during the summer but still maintaining some vegetation for the smaller fish. After the bloom starts in my pond, it clears up nicely, 18" to 24", and stays that way till winter. I just need to clear enough to get the bloom going and to get the fish biting again. I'll go order some more alum Monday. Thanks again for the input, I truly appreciate it. One day maybe I'll be smart enough to give somebody else some advice on this pond stuff.