Rainman I respectfully have to disagree. This is my pond at age 2 with no plants to speak of for algae control. What it does have though is the algae eaters mentioned below. An open pond like this will fill rapidly with FA. This pond started to fill with FA this spring because the algae eaters were all dead from the winter fish kill. Only when the plants came up did the algae disappear. So plants or algae eaters by themselves or in combinations can eliminate FA. I can tell you that I have watched KOI and Israeli Carp eat FA hundreds of time. I have never seen a Channel Catfish eat algae because I never see them unless I feeding them with some pellets. But Zetts said they did. And I was at a pond seminar talking to a guy that used to not have FA and now did. I told him that Zetts used the three algae eaters including CC. Then he said that he had been clearing his pond of CC and that’s when his algae started. If you Google "will KOI eat algae" you will find many links saying yes.
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From the very beginning 16 years ago when I built my pond the objective was to eliminate Filamentous Algae without using chemicals or dyes. The pond over those years has taken on different forms but each kind of this changing pond never had an FA problem and has never had a chemical in it. Most of the ideas that made this happen came from Andrew J Zetts of Zetts Fish Farm & Hatcheries, Drifting, PA.
The pond in the first picture is algae free and is about 2 years old. The algae fish eaters were 20 KOI, 6 Israeli carp, and 100 Channel Cats. Others were bass & bluegill.
http://answers.yahoo.com/question/index?qid=20100404200455AAogY8qhttp://answers.yahoo.com/question/index?qid=20100105205617AA73Fifhttp://wiki.answers.com/Q/What_do_Koi_Fish_eat
