Generally these are long filaments, strands, or nets of plant material that may form floating nets. Many people refer to excessive algae growth as "pond scum" or "pond moss."
These are microscopic free floating plants that provides a green, bluish-green, or brown color to the water.
Commonly referred to as "muskgrass." This form of algae grows from the bottom and has leaf like projections occurring around a stem. When crushed between the fingers, this algae feels gritty and has a distinctive musky odor.
Nitella is closely related to chara, but generally is found in deeper waters. Nitella is easily distinguished from chara by lacking the garlic or musty odor associated with chara.