John,

There are many articles in the archives on this topic but IMHO it all comes down to this....if you have an overload of nutrients SOMETHING is going to come along and take advantage of that. If some sort of native and/or introduced plant isn't drawing out the nutrients then you're going to have algae.

People will nuke their ponds to kill off the plant growth but again in my opinion that's a never ending battle. The nutrients are there....my solution has been to try to cultivate enough plants that the algae is curbed naturally. I don't always succeed but that's what I try to do.

Dale

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"When tempted to fight fire with fire, remember that the Fire Department usually uses water." - anonymous