Algae Control for Fish Ponds and Water Gardens

Algae can be a real nuisance, it detracts from the beauty of your water feature and is hard to control. When we talk about algae we always say “algae control“, and that’s because it is always present in bodies of water that are outside. Algae spores are carried into the water by wind, rain, runoff from surrounding areas, and even animals can deposit them in the water just by stopping by for a drink. So how do you control it? The first thing to do is to understand it better.

Green water algaeHow about a little biology, I know – your not in high school anymore, so don’t worry, there is no quiz. Algae comes in a variety of forms from single cell organisms to more complex cell structures. It needs water, warmth, and lots of sunlight. It also needs nitrogen and phosphates to grow. Since your water feature or pond is likely to be outside it’s a sure bet that it’s getting what it needs during the warm months of the year to thrive. It is also very vigilant, it doesn’t take long for it to completely take over.

There are several types of algae, but the ones you are most likely to have in your water garden or pond is string algae and green water algae. There are scientific names for them that are difficult to pronounce, not to mention remember, so we will omit them here. String algae gets its name because it forms strings with it’s colonies or a mat of algae when on the surface, which can be scooped out of the water with a net. But green water algae is the hardest to get rid of, it will turn your water green. This is called algae bloom. It will turn so green in fact that you will not be able to see any deeper than the surface of the water if not put in check. It can even reduce the levels of sunlight that penetrates the surface to such a level that it chokes out underwater plants. That’s ugly, and who wants ugly?

So what do you do? There are a lot of ways to control algae, the best way is to have a complete and balanced ecosystem in place that will counter act algae blooms before they begin. But for the average water gardener that may not be possible due to size constraints. The best way to attack the problem is to prevent it. So how do you do that? First realize that fish, birds, fecal matter, dead plants, decaying fish or bugs, leaves, grass and twigs all contribute to excessive nutrients (nitrogen and phosphates) that algae require for growth. Planting water plants that help deplete the nitrogen and phosphates in your water will go a long way to help prevent algae growth. Oxygenators and other underwater plants do a great job at this, because nitrogen and phosphates are what they use to grow. Another great plant to use is floatingString Algae water plants, their roots are not confined by soil under the water and draw nitrogen and phosphates directly out of the water without having to filter it through the soil. Other water plants, like water lilies and lotus, also do a good job with this and help maintain the balance. Another benefit is the shade that plants add to the waters surface. Water lilies are great providers of shade and so is the lotus. Just make sure to choose the right ones for your climate.

Marginal water plants will supplement the other water plants as well, like rush, cat tails, swamp grasses, and many more. All these plants help reduce the nitrogen and phosphates in the water and deprive the algae of the breeding ground it needs.

Another source of algae control is bacteria, I know, no more biology, right? But, bacteria is present everywhere, and having the right bacteria in your pond keeps it healthy by breaking down waste and decaying plant matter, which provide the nitrogen and phosphates that we have already talked so much about. The bacteria that you need can easily be added, or supplemented. If your just starting your water garden or pond you can add the bacteria in a powder or liquid form which you can get from you pond supplier. Small and medium ponds and gardens should get a new dose of bacteria in the spring once the water temperature reaches and maintains at least 60 degrees Fahrenheit.

You can also control algae using barley straw bags or barley straw mats in your pond. These mats and bags of barley give the bacteria a place to form it’s colonies were they decompose the barley straw adding a natural algae inhibitor to the water in the process. You can also get barley extract to add to your water if you don’t want to mess with decaying barley straw, but barley straw is usually only effective for small to medium ponds of 3000 gallons or less and need to be added and removed on a rotational basis to maintain the process, which might be a little more of a hassle than the average pond or water gardener wants to maintain.

For quick results, like getting green water under control, try AlgaeFix. It’s safe for fish and pond plants and will take care of your algae problem fast. But, it’s not the solution to maintaining the water quality, it’s more like a bandage until the other control strategies have time to effect a natural balance.

Use a combination of all of these, the plants and bacteria, to control your algae problems. These measures will take time however, the plants need time to mature in order to have an impact on the algae. Enjoy your home improvement projects.