From the multiple types of algae that can grow in your pond, here are the most common types:
Filamentous algae is most common, growing in mats and strings.
Planktonic algae causes green water, it has millions of cells that cloud together.
Chara algae is weed-like, it grows like a carpet along the bottom.
Cattails & Other Emergent Plants - Emergent plants grow around the perimeter of a pond in shallow water with all or most of their foliage above water. Examples are Cattails, Bulrush, Reeds, Purple Loose Strife, Pennywart and Pickeralwood.
Pondweeds - The pondweed family has over a dozen varieties with these four being the most common: Sago, Clasping Leaf, Curly Leaf, Large Leaf.
Elodea - This plant grows in thick clumps and is usually not a big problem, the leaves are in whorls of three around the stem.
Duckweed & Watermeal - Duckweed is hard to control, it forms a thin layer over the surface in calm ponds. It will not grow well in moving water so use of a surface aerator will help in controlling growth.
Waterlilies - Waterlilies can become a problem in many ponds, they grow off of a large central root system (much like popal trees). Some growth is great for shade and cover for fish, but when left unchecked they will overpopulate quickly.
Eurasian Milfoil - Spreads very easy since fragments of plant can re-root and grow. Do not try to remove by raking.
Other Less Common Weeds: Include Naiad, Coontail, Bladderwort, Hyrdilla, Parrot Feather & Water Hyacinth.
Many states restrict the shipment of EPA registered chemicals into the state. At this time most products that are not EPA registered are not restricted. Please look next to each product to see if it is EPA registered. If it is, please consult the information below to see if it can be shipped into your state: ¥ AK, CA, CT, ID, HI, ME, MA, NH, NJ, NY, RI, VT & WA restrict the shipment of products into their states. Products can be bought from within the state but not shipped in. ¥ No products can be shipped into Canada. Canadian law requires different labeling and registration. US labeled chemicals cannot ship into Canada. ¥ GreenClean (GC20, GC50) can be purchased in NY but you must obtain a permit to apply in that state, all other states ok. GreenClean Pro (GC50PRO) and GreenClean Liquid (GCL5) are restricted in MA. The states of NY, NJ, VT and ME can buy GreenClean Liquid (GCL5) but must obtain a license to apply in that state.