Q: We just bought a small acreage with a beautiful pond, but now it's all covered with lime green slime! What can we do?
A: The lime green, slimy pond scum you see is algae, which often bloom in the early months of spring. Pond algae can be found either floating on the pond surface or attached to aquatic plants, bottom sediments, or other hard surfaces. Microscopic algae are the most common type of algae; excessive blooms of the tiny free-floating algae give pond water its characteristic green color.
It's always best to stay ahead of any algae problem, and there are several things you can do before algae get out of control. Algae need three things to grow and "bloom": nutrients, sunlight, and warm water. The nutrients can come from fertilizer, septic systems, geese, or other animals. As a filtering and preventive measure, it's a good idea to plant a buffer strip of long grass and vegetation around the edge of the pond. This will help remove the nutrients before they reach the water and cause a problem.
Q: How can we tell if our farm pond is safe for swimming?
A: A dip in the pond can be a welcome relief on a hot day, but it's good to know what you're jumping into. Bob Broz, an extension water quality specialist at the University of Missouri, says pond water often has waterborne pathogens, but it's generally not necessary to test for bacteria.
It is important, however, to determine where your pond water comes from and what it flows over before it gets to your pond. "If the water runs through a feedlot and gets into the pond, then the chances are very good you'll have exceptionally high levels of bacteria, and you may want to check it," Broz says. "But most of the time we know that you're going to be above what we would classify as a safe limit for a public beach for swimming."
Before jumping in, do a visual inspection of the water's surface. If you see green or brown scum, an oily sheen, or floating dead fish, do not go in the water. Although most algae blooms aren't harmful to humans, it's not very pleasant to swim among them. Never drink or swallow pond water. Be sure to stay out of the water if you have an open wound that could get infected.
Also make sure everyone knows general safety rules for swimming. Have a pole to reach out to struggling swimmers or a float to throw. Put up signs to label swimming areas and mark the water depth in different spots.
Q: Can I fish in the pond on my acreage?
A: Yes, you most likely can. Ponds are great starting points for beginner fishers and relaxed afternoons. If you plan on fishing for sport often, consider stocking your pond. Follow recommended state fishing guidelines for your sized pond. Creel limits determine how many fish you can remove from a body of water in order to keep the natural status quo in place.
Q: How can I make the water in my pond clear?
A: Aeration, bacterial treatments, pond dye, and phytofiltration will all make your water cleaner and clearer. Waterfalls and floating fountains will aerate your pond by infusing air throughout, and result in less algae and odors. Natural bacterias are beneficial for your pond when they break down muck and nutrient loads. Adding bacterial treatments to your pond will improve water quality in an aerated pond. Pond dye limits the amound of sunight that penetrates the water, which reduces the growth of algae and weeds. Pond dye will also create a pleasing reflective appearance on the water's surface. Phytofiltration is natural plant filtration that removes extra nutrients. Aquatic plants like hibiscus, water willow, and water snowball are perfect for nutrient reduction and can be set up on floating islands for added beauty.