Algae and weed control was at the top of the questions at the Expo There are literally thousands of algae species and the most common asked about is the filamentous string algae. For weed problems the most asked about was Eurasian Watermilfoill which is an invasive (nuisance) species taking over ponds and lakes across the nation.
Algae and weeds, where do they come from? How do they grow? Why my pond or lake? Plants need three items to live. Similar to the fire triangle where we need a Fuel source, Heat and Oxygen to have fire, we can take one of the 3 sides out and knock down the flame.
Weeds and Algae need Nutrients, Water and Photosynthesis (sunlight) to live. 
Taking away one of the three sides can knock down the weeds. Let’s back up a little to explain the word weed. In the beginning they were actually plants such as the Lilly pad (just as an example), it looked great during the blooming season, blocked sunlight from the water and provided habitat for our fish and microscopic insects for the little fish.
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