String or hair algae is a very common form of algae that occurs in most ponds and the growth rate is related to nutrient load, and other factors, within the pond (high nutrients=high growth rate, low nutrients=low growth rate). These types of algae growth can actually be expected in the Northeast area in the early spring and late fall, and are completely normal. The goal is to not to have this type of growth occurring at other time of the year as it can be very unsightly and difficult to control. The blooms that occur in the spring and fall will usually clear up on their own, but for those times of year that these growths happen there are various treatments that can be applied to the pond that help to control and clear these growths. The products that are available are pretty numerous and some work, some don’t. On the FSA website there is a page that lists our “Preferred Water Treatments” and suggests products that we have found to work very well.The BEST method of all types of algae control is the use of aquatic plants in the pond. Algae is a very basic plant and without any type of competition from more complex plants such as lilies, iris, and the numerous other aquatic plants available to pond keepers; algae will run amuck in any pond system. Provide more plants to compete for the algae’s food source and the algae will starve and die off naturally, without the use of treatments or chemicals, at the same time beautifying your pond, creating habitat, and attracting desirable wildlife.The basics of keeping your filters clean help very much in algae control of all types of algae. Ultraviolet filtration does NOTHING to help control string algae.There are some types of fish that can do a very good job at algae control as well, one of them being the “Chinese high-fin shark”, it is not Chinese and not a shark of course, and will live in peace with your pond fish; they do a great job at eating algae and scraping the rockwork. The Chinese shark is cold hardy as well and can survive the winters. I have seen people use some of the tropical algae eating fish such as plecostomus to help in algae control and they certainly help as well, but the trick is to get them out of the pond before the cold weather sets in as they will NOT handle the winter months and need to be moved indoors for the winter.I like to use a combination of all methods. I use plenty of aquatic plants along with the treatments that are available, and make sure that my filter pads are cleaned regularly. The treatments are used more as a preventative about once a month whether I have string algae or not. When it comes time for you to do your treatment, try to remove as much of the unwanted algae growth as possible, by hand, then apply your treatments. After you have done the treatment it is good practice to give a very good cleaning to your filter pads soon after, as most treatments breakup the algae and it will ultimately end up in your filter material.