The 5 Most Commonly Asked Questions About Algae
1. What is algae and how does it get into my pond? Algae is a simple water plant. It comes in many different shapes and sizes, from algae that are microscopic to those that cluster together in slimy clumps or hair-like mats. Even seaweed you see along the ocean shore is algae. Algae finds its way into your pond via plants you bring in, birds, or other animals that bathe in the pond or waterfall.
There are several types of algae. free-floating algae that makes your water look green is prevalent in the first 90 days after a pond is completed. It indicates a high carbon dioxide and low oxygen content in the water.
Hair algae consists of big clumps of long, stringy algae. This is the result of nutrient build up in your pond. This algae is fairly easy for you to remove by hand. Doing so helps to eliminate the nutrients in your pond. However, you might also consider reducing the food you feed your fish, or even the number of fish you have in the pond. Introducing plants along the border of the pond or within it such as more lilies, or water hyacinth and other oxygenating plants will help to eliminate nutrients from building up in your pond.
Slime is easily recognized as the green growth on the sides of the pond. It may look unappealing however, it produces as much as 60% of the oxygen in your pond. Your fish and other insects and invertebrates within the pond need this. Your pond will not be fully balanced without it. So there really is something positive about algae.
2. Is algae good or bad for the pond or waterfall?Both. Algae within a balanced system is a good thing. It provides food for small microorganisms that then become food for insects, which then become food for fish, amphibians, and birds. Algae also produces oxygen within the water.
Algae is unattractive to many when it turns a nice clear pond into a dull green opaque pool that muddies the view of fish and plants.
3. What causes algae to flourish in the summer?Algae exists all year long within ponds and waterfalls. What makes it more abundant during the summer months is due to a combination of factors. Increased sunlignt, warmer temperatures, and nutrients contribute to what are called "algal blooms' in ponds.
Over time organic material builds up in ponds from fish and other animal waste, as well as from plant debris that falls into the pond. All of these are good sources of nutrients such as nitrogen, phosphorous, and carbon- the very chemicals algae needs to grow. Increased temperatures and sunlight further encourage algal growth by providing the best growing conditions. Add to this the potential for yard fertilizer to run-off into your pond or waterfall adding even more nutrients, and you have everything algae could ever want to grow vigorously and reproduce.
The problem with algal blooms, beside the lack of visual appeal, is they cause the amount of dissolved oxygen to drop in the pond. Even though algae is a plant and generates a lot of oxygen, when the algae die off decomposition kicks in. Bacteria break the dead algae down using up a lot of oxygen in the process. When the oxygen levels drop. fish and other aquatic organisms suffer and may even die.
4. What can be done to get rid of algae?You can control algae by placing plants within the pond. Plants such as water hyncinth, water lettece, water lilies, cattails, bulrush, and many other types of wetland plants pull nutrients from the pond water in order to grow and reproduce. They also help to put oxygen back into the water. Other floating and submerged plants are commonly referred to as oxygenators because they continuously release oxygen into the water as part of photosynthesis.
Planting trees along the edge of the pond, or placing water lilies and other floating or emergent vegetation within the pond, can provide shade which will reduce both the amount of sunlight and the temperature of the water, reducing the growth of algae.
A waterfall or stream running into a pond help to add oxygen to the water. This may be something to consider when planning to build a pond. The action of running water continuously adds oxygen to the water offsetting the loss of oxygen from decomposition.
Chemicals can also be used to rid a pond of algae. Some are fish safe, some are not. If you want a crystal clear pond and no fish, chemicals similar to those used for swimming pools may be an option for you. If you have fish then purchase fish-safe chemicals. keep in mind that most of these chemicals although fish-safe because they do damage or kill the fish, may reduce the amount of dissolved oxygen. This will then stress the fish. Read the instructions carefully, and consider removing the algal debris once it drops to the bottom of the pond in order to prevent oxygen loss from decomposition.
5. How can I keep algae from recurring in the pond?You can't. But by incorporating plants, shade, and certain safe chemicals, you can keep the algae under control.
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