Building your own backyard pond gives you the most freedom to truly have the pond of your dreams. But don’t let your creativity cause problems for you later on. Do your research and don’t let these common mistakes when building a pond cripple your design.
Making Your Pond Too Small
Your pond will and feel quite big during the digging process. However, people often forget that the depth of the hole you dig for your backyard pond will not be the depth of the water. Your pond’s water level will end up being 4”-6” below the top edge of the ground surface that you’re digging. This discrepancy is due to evaporation and other factors such as the natural contours of the ground.
Why would your pond’s water depth matter? If you are looking to keep your fish in your pond over winter in a cold climate, your pond should be at least 2 to 2½ feet deep. For this pond water depth, you must dig a hole that measures at least 2½ to 3 feet deep for your pond. Otherwise, your pond will be too shallow to sustain fish year round throughout most of Canada.
Not Factoring Rock Into Pond Size
If you are trying to hide your pond liner, you will want to layer rock and gravel on the bottom and the sides of your pond. Once you’ve added this decorative rock around your pond’s edges, your pond will appear a foot or so smaller than your bare liner did. If you are adding rocks to hide your pond liner, these will take approximately 6”-8” off of each pond side and about 6” to 12” out of the overall depth of your pond. Be sure to take this into consideration when calculating what your pond’s dimensions should be.
Building Narrow Ledges or No Ledges at All
Not building ledges or shelves into your backyard pond is a big mistake. Without a shelf, you have nowhere to house your marginal plants, which add decorative character and practical function in your garden pond.
Many popular pond plants - like cattails, rushes, and irises - are marginals, which need close proximity to the surface of your pond, preferring placement anywhere from 6” to 1½’ from the water surface. Most backyard ponds are deeper than this, so marginal pond plants require a supportive ledge. A ledge or gradation to the middle of your pond reflects ponds in the wild, for this function and a naturalistic aesthetic quality.
Don’t forget to consider your pond’s ledge size. If your ledge is only a foot across and you decorate your pond edge with medium to large rocks, you are left with little to no room on your pond ledge for your marginal plants. We recommend you make your ledges around 18” to 24” wide so that your pond marginal plants have sufficient room.
Making Your Pond Sides Too Steep
If you make the sides of your garden pond too vertical, stacking rocks to create a natural pond edge becomes difficult. A gentle slope on your pond’s outer edge permits piled rocks to stay in place more effectively than pond sides that are straight up and down.
Under-sizing Your Pump
Running a pump that is too small for your pond is one of the most common mistakes when building a pond. The inadequate water flow caused by an undersize pump will undoubtedly plague your pond with algae, fish health issues, and possible pond overheating.
Do your research to determine what size of pump you will need for the size of pond you want to install. Figure in your pond’s head height, water volume, and whether or not there are fish in the pond. It is always better to go with a larger pond pump than one that is too small. (For help calculating your pond's pump needs, here are some helpful pond calculators)
Providing Insufficient Filtration
If your pond has fish or if it is in area that gets a lot of wind, you will have more accumulation of debris and waste in your pond. Choosing a filter that sufficiently cleans your pond is essential. Without one, you will likely deal with a build-up of toxins that could wipe out your fish or you will be cleaning your pond out daily. Proper filtration is the key to having a healthy, happy pond.
Your clean-up crew should consist of a skimmer filter for debris and a sufficiently sized bio-filter for processing waste. Just as with your pump, your pond size, depth, layout, and bio-load are all important factors when choosing your filter.
Putting the Pond in a Poor Location
It might seem like common sense, but make sure that your pond is visible from the place where you want to see it (kitchen window, deck, yard). Avoid putting your garden pond in a place that will collect large amounts of debris, such as near trees. It can quickly become frustrating if you are constantly cleaning and skimming out debris just to maintain a nice, clean pond. Also, try to ensure your pond has some wind and sun protection. Strong gusts of wind can litter your pond with debris and empty your pond water. Direct sun can affect algal blooms and overheat your pond.
Underestimating the Amount of Work Required
Building and maintaining a pond is a lot of work. If you have a bad back, don’t particularly enjoy digging or working outdoors, either hire the work out or try to put together a working-party to split the job. It’s not uncommon for people to get halfway through installing their pond and then to bail on the process because they underestimated the amount of work required.
Building your own garden pond can be incredibly rewarding. But to make the most of your time and effort, avoid these common mistakes when building a pond. With the proper research and planning, the backyard pond of your dreams is within your reach.