Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Green slime - newbie question

What you've got is FA (Filamentous Algae). Its caused primarily from having to many nutrients in your water. There are several ways to deal with it.

You can use chemicals, which could be costly to treat the entire pond, and if not careful can do harm to your fish if treated too aggressively, depending on what you use.

You can try to get some better plants growing (American pond weed, arrowhead, iris, even some types of Lilly pads) to help use up some more nutrients.

You can add pond dye to reduce sunlight penetration.

Aeration to dissolve some of the nutrient gases will also help over time.

You can try the quick aggressive way or the slow, more natural method.

I'm sure you'll get other suggestions as well.