Building a Backyard Oasis

More and more homeowners are jumping in to the water gardening hobby. People are spending more time outside the home -- expanding their areas of entertainment and relaxation to the patio or deck, and enjoying the sound of soothing water, the sight of swimming fish and the envy of their neighbors.

You, too, can get in on the fun. This article is designed to help you choose a location for your water garden retreat, design a pond that will reflect your personal style and tastes, build a pond that will last a long time, and complement it with the right equipment.

Choose the Right Location

While determining the location for your pond, consider its proximity to your house, nearby electrical sources and landscaping. Building the pond near your home makes the pond the center of attention, a place where your family and friends can enjoy it the most while relaxing and entertaining. Access to a nearby electrical source is necessary to power equipment - filters, pumps, ultraviolet (UV) clarifiers and winter de-icers - and will keep pond inhabitants healthy year round.

Decide whether you want an in-ground or above-ground pond. Either way, it should be at least 18 inches deep and have no sharp or rough edges that can harm or injure fish as they swim about. In-ground ponds can be constructed using preformed ponds or flexible liners. Flexible liners are ideal in terms of price, ease of installation and durability, and offer a host of free-forming shapes.

When choosing the appropriate landscape for your pond, consider the following:

Planning the vision: Learn all you can about the various styles, sizes, shapes and water features available for ponds. Investing the time at this stage is well spent; it will save you time, money and energy in the long run. Choose the pond size, shape and products that best meet your needs.

Location: Install the pond in an area that can be viewed from rooms where you will spend a lot of time. When considering the landscape, remember that a pond doesn't have to be on a flat terrain; you can place it on varying, sloping surfaces. Incorporating these landscapes can create unique, interesting features.

Amount of sunlight: Five to six hours a day is ideal. Excess sun causes an overabundance of algae and green water. Conversely, shade trees drop leaves and blossoms into the pond, robbing the water of oxygen as they decompose. If possible, try for a happy medium.

Designing Your Pond

Once you have decided on a location, you can design the size and shape of your pond. While the design will depend mostly upon personal preferences, you must also consider the size of the garden and the type of fish you'll keep in it. Koi ponds, for example, are usually deeper than typical garden ponds and have a larger external filter. By contrast, a wildlife pond will be much shallower and may have few or no fish as well as less water movement.

When designing your pond, consider the three "S"s - size, shape and safety:

Size: As a general rule, bigger is better. Make your pond at least 30 square feet, with a depth of 18 inches or more. Ponds of this size tend to be easier to care for and will be more ecologically balanced, retain more stable temperatures and provide greater movement for fish. The water's depth is particularly important in cool climates where ice can form on the water's surface. In areas that experience cold winters, a 30-inch or greater depth is recommended to protect fish well into the spring.

Shape: The shape and layout will reflect personal tastes and surroundings. Formal gardens are characterized by geometrically shaped ponds with bricks or flat paving stones around the perimeter. Informal garden ponds have more natural, free-form shapes bordered with stones of various sizes and shapes. It's best to avoid tight curves or intricate shapes because they tend to waste lining material, reduce water capacity and create stagnant areas where solid wastes accumulate in the pond.

Safety: Because ponds possess a magical attraction for children, it's crucial to incorporate safety measures. Reduce children's access by building a raised pond or a fence around the pond's perimeter. Alternatively, you can design the pond layout with shallow zones that outline the perimeter. A shallow zone that measures one to two feet wide and four to eight inches deep can help prevent children from coming in contact with the deeper water located in the center of the pond. Create a natural barrier to inquisitive children by landscaping with large stones, boulders and tall, marginal plants.

Six Steps to Build a Pond

There are three basic methods to install a garden pond: concrete, preformed ponds and flexible liners. Liners come in weights ranging from tear-resistant, lightweight liners to heavy-duty EPDM liners.

So, what size liner is best? Here are two good rules of thumb to calculate liner size:

Liner length = Pond length (2 x avg. depth) 2 ft. overlap.
Liner width = Pond width (2 x avg. depth) 2 ft. overlap.

Note: The pond should be at least 30 sq. ft. with a minimum depth of 18 inches.

You can make the pond-installation process relatively simple, and extremely enjoyable, by following these six easy steps:

Step 1: Layout
Use a heavy garden hose or rope to outline the pond's edges. Place short stakes at one-foot intervals to retain the desired shape. Then make any final adjustments before digging.

Step 2: Excavation
To excavate the pond area, start digging in the middle and work outward to avoid breaking the pond's edges. Create two or three tiers in the pond - the top one for edging and the others for plant shelves. Deep areas should be between 18 and 40 inches in depth, depending on the climate, and shallow areas should be between four and 12 inches. In most of the United States, 18 to 24 inches is generally a good depth. Be sure to check the depth and the layout plan regularly to avoid any unnecessary digging. To keep the surface of the pond level, stake out strings lengthwise and widthwise using a line level.

Step 3: Padding and Underlayment
Carefully remove all sharp objects from the surface, such as nails, twigs, rocks and protruding roots that could puncture the layer. Line the entire pond with one to three inches of sand, then properly position the underlayment material to protect the main liner from root and rock punctures. Other underlining options include carpet padding and newspaper, but they won't provide the same degree of protection. The underliner is crucial - even if the soil appears free of sharp objects, which can work their way to the surface as the excavation settles.

Step 4: Liner Installation
Unfold the liner on the lawn or another flat surface nearby. With at least one person on either side of the liner (more for a larger liner), pick it up and walk to slide it over the pond. Let the liner drop into the pond, making sure it extends evenly, well beyond the perimeter. Minimize the number of small folds by pulling or tucking them into the large folds. Hold the liner in place with bricks or rocks and fill the pond with water. This will cause the liner to conform to the pond's shape.

Step 5: Rock Borders
For a natural water garden pond, build a rock border around the edges, allowing rocks to overhang the water by one or two inches. To prevent the liner from showing, make sure the water meets the rock edging. Simply extend the liner up behind the edging and backfill with soil or rocks to create a barrier that securely holds the liner upright and prevents both drainage and runoff. After the pond is completely filled and the rock edging is in place, trim any excess liner.

Step 6: Equipment Installation and Finishing Touches
If the pond is filled with municipal tap water, the pond should be treated with a quality water conditioner to remove any potentially dangerous chlorine and chloramines. And in order to help keep the pond clear and healthy, incorporate a UV clarifier with the type of filtration system that best fits the pond's size and water features.

As a self-contained ecosystem, a pond needs a means to remove toxic waste; the more fish in the pond, the greater the demand on the filtration system. A koi pond requires water that is constantly filtered and re-circulated, maintaining a stable pH, very low ammonia, nitrite and nitrate levels, and adequate levels of oxygen.

By taking in carbon dioxide and releasing oxygen, aquatic plants provide essential oxygen that fish need to survive. During the decomposition of organic material (i.e., decaying plant fragments and uneaten food) and fish waste products, harmful ammonia is produced. Beneficial nitrifying bacteria convert ammonia to nitrates, which are relatively harmless to fish and beneficial for plant consumption. The ecosystem is balanced when enough nitrifying bacteria are present to control ammonia and nitrite levels, and enough plants are present to control nitrate levels.

There are two basic types of filtration systems to clean pond water:

Mechanical - uses foam filters to physically trap dirt and debris.
Biological - uses natural biological processes to improve the water and create an environment for beneficial bacteria to colonize. These bacteria convert harmful ammonia from waste products into nitrates, which are relatively harmless to fish and beneficial to plants.

Filters with specific functions can be installed and connected separately, or you can buy filters that provide a combination of filtration systems to simplify installation and maintenance. For example, mechanical and biological filtration systems are available in one unit; and some offer the option of a UV clarifier. Understanding the filtration types of particular-sized ponds is key to determining your maintenance duties and frequency.

Decide whether a submersible or external filter is best for your needs, so you can incorporate it and the necessary plumbing into your excavation and landscaping plans. Submersible filters are placed into the pond and can be hidden by aquatic plants. External filters are placed out of the pond and, with proper planning, can be hidden with beautiful landscaping or stones. Some filters, such as pressurized filters, are designed to be buried for concealment. External filters are recommended because they are more effective and easier to clean.

A Few Finishing Touches

If you live in a southern climate, add plants to your pond as a finishing touch. Then wait several days and add fish a few at a time over the course of 30 days to ensure the pond and filter are biologically ready to support aquatic life.

Select healthy plants that will not outgrow the pond. Plan to have a ratio of one bunch of six strands of oxygenating plants (e.g., Anacharis) to every two square feet of water surface area to reduce or eliminate any algae. Pot all plants to control their growth and allow easier maintenance. Fill the plant basket half full with soil and press down to remove air pockets. Place the plant in the basket so that the base of the growth buds is level with the basket's rim. Add soil until it's within one inch of the top. Press firmly and then add one inch of coarse, lime-free gravel to prevent fish digging.

Landscape the pond to maximize its appeal. Dress up the water garden habitat with water features, lighting systems, planters, sitting areas and other enhancements.

Water gardening can be a fun, relaxing and rewarding hobby. Of course, the more homework you do upfront, the more beneficial the experience. Jump in and enjoy!