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.


Plants For Your Water Garden

Water Gardening can be as simple or as complex as you want. The simple water garden is good for the small pond, and more complex water gardening is best reserved for the large water garden. The most obvious reason is space, which will define how much diversity a pond can contain and sustain. If you’re a beginner, I would suggest keeping it simple to start with so you can get a good idea of how your plants will develop and the space they need. It is easy to expand later on after you grasp the basics.

There are six categories of water plants that you should familiarize yourself with. These are: Submerged Plants and Oxygenators, Floating Water Plants, Water Lilies, Marginals, Water-Lily-Like Plants, and Lotuses.

Hardy Water Lily

In keeping with the simple and easy water garden, we will focus on three of these categories. You can add from the other categories as space and your expertise accumulates.

Water Lilies. I have chosen this category first because of their visual impact. Water Lilies are among the favorites of water gardeners and you should think about including them in your garden as well. Water Lilies are broken down into two groups: hardy and tropical. Hardy water lilies survive cold climates and winter well where as tropicals must have special care to keep from freezing. You can tell them apart because of their leaves, hardy ones have smooth edges on their leaves and tropicals have a crinkled appearance. Also hardy lily blooms open during the day and close at night while most tropical ones open at night and close again in the early to mid morning hours. Tropicals also have a stronger scent then the hardy variety. Most water lilies grow in 3 to 4 foot depths, but they do quite well in ponds with only 6 to 18 inches of water. If you live in a climate that often freezes your ponds surface during the winter, plant your lilies below the level of the ice. This will protect their roots from freezing and allow them to flourish again in the spring. Also, if freezing is the issue, use water lilies from the hardy variety. Since water lilies from both groups offer a wide selection of color, you can easily find the plants you want without sacrifice.Floating Water Plant, Eichhornia Crassipes

Floating Water Plants. Floating water plants are those that sit on the surface with no need of having their roots in soil to get their nutrients. Their roots simply dangle beneath them and collect nitrogen and phosphates from the water that could otherwise cause an algae bloom. These are extremely easy to grow plants, and some even have blue blooms. Although some are winter hardy, most are not. They are the cheapest of all water plants to have so treat them as annuals. Since they are rich in nitrogen and phosphates, (which they extract from the water), you can add them to your compost pile and make great natural fertilizer for the rest of your garden. They are prolific growers and can take over you pond quickly, so you will want to thin them out in mid season and as often as needed.

Water-Lily-Like Plant, Ranunculus aquatilisWater-Lily-Like Plants. These plants grow in soil from 1 inch to 2 feet below the water surface. They grow with their leaves and blossoms on the surface like lilies but are botanically different, so they are classified differently. Examples are Hawthorn and Frogbit. These plants also have wonderful blooms and will add contrast and variety to your water garden.

Water plants are easy to plant. You will need containers for your lily and lily-like water plants and your floating water plants need nothing at all. Also, if you intend to add fish to your pond, it is a good idea to cover the soil in your containers with small river stone or a simple wire or nylon mesh (1 inch chicken wire or bird wire works well). This will prevent the fish from digging in your containers to get at the plant roots (which they love to eat). Water plants are easy to take care of as well; usually just a little thinning out is all that is required. An added benefit of water plants is that they reduce nitrogen and phosphates in the water and provide shade, all of which will reduce ugly green algae. Once the planting is done, your ready to start enjoying your water garden.

Water Gardening is easy and fun, and can provide your garden with beauty for years to come. Have fun with your home improvement projects.