>I've seen where people have tried two or three times to clear the water, and after the next application BAM, the water clears like >magic. I think it's all about getting the correct amount of stuff in the pond. Calculating water volume is a hard thing to do in a pond!
You hit the nail on the head. Not using enough alum will fail to clear it every time. Blaming other things just takes you on a wild goose chase. Not saying to just add alum until the water clears, because runoff ponds can easily become too acidic. As long as water is pH 7 or above, you can probably safely add alum until it clears up.
