How to Build a Pond – A Beginners Guide to Building the Perfect Backyard Pond

For weeks now you’ve been eyeing the perfect location for a pond in your backyard. You may even have pictured how it will look – a spectacular pond that will impress the neighbors and add to the value of your house. But now that you know you want a pond, where do you go from here?

Thankfully, planning and building a pond isn’t overly difficult and if you follow the information in this article, installing a pond will be an easy and rewarding process.

Location of a Pond

Ponds have a lot in common with real estate, and it’s all about location, location, location. So where should your put a pond?

Don’t place it underneath trees – While a pond nestled under the branches of a mature tree may look like the perfect location, it’s a really bad place for a pond. The reason for this is simple – leaves will continually fall into the pond water throughout the summer and into the fall season.

And when leaves fall into water, they quickly start to decay and break down – which causes a huge spike in ammonia. For those familiar with aquariums, you may know that ammonia is dangerous for fish, and at best it will irritate the gills on any fish in the water. At worst it will simply kill everything – and I mean everything in the pond if it builds up enough in the water.

Choose a level site – Unless you have the money to construct retaining walls, or want to engage in large scale excavation to terrace a hilly area in your backyard, you should always plan to put your pond on a flat area.

Choose a site with sunlight – but not too much – A pond should always be placed in an area where it receives some direct sunlight during the day. In an ideal location, it would receive sunlight for approximately half the day, and spend the rest of the day in shade.

The direct sunlight will help with plant growth in the pond, and by spending part of the day in shade, it will help to limit algae growth. If you choose to place your pond in an area where it receives sunlight for most, or all of the day, your pond will quickly start to look like pea soup.

Place it close to the house – Placing a pond close to your house isn’t an absolute requirement, but it does bring some benefits. If a pond is located close to your house, it’s far easier to keep an eye on it.

Whether it’s identifying pests that are causing problems with the pond, or dealing with maintenance issues, it’s always easier if it’s closer to your house under your watchful eye. Plus, isn’t a pond more fun when it’s close to a patio or deck, and doesn’t take 10 minute to slog out to it?

Call before you dig – If you take anything away from this article, it should be this – always call locate services before you start to dig a pond. You must determine if there are any buried power lines, gas lines or anything else that can cause serious injury or even death before you start to dig a pond.

Size of a Pond

The size of your pond will influence what kind of plants and fish you can have, and more importantly – how much maintenance it will require.

Small (10-50 Gallon, 38 -190 Litre)

A small pond is the perfect way to get into the hobby and doesn’t require much in the way of effort or maintenance. With a pond this small, you really limit yourself to small fish like rosy red minnows or mosquito fish (no goldfish!) and small aquatic plants.

But it makes the perfect addition to any backyard patio or landscaping, and will give you a chance to get your “feet wet” so to speak. Many people start with a small pond and quickly upgrade to larger one once they discover the fun and serenity that a pond brings to a back yard.

Medium (50-1000 Gallons, 190 -3785 Litre)

This size is really where ponds come into their own, and they allow a wide diversity of plant and animal life in the pond. For a pond this size, you will need to carefully consider filtration and where you locate it becomes far more important.

For a pond this size, there still isn’t a lot of maintenance, but you do need to be more involved than with a small pond – especially if you have goldfish in the pond.

Large (1000 Gallons +, 3785 Litres +)

There really is no limit when it comes to creating ponds, so the large category encompasses everything from 1000 gallon (3785 litre) ponds, to what could almost be considered mini lakes. These ponds truly let you create an oasis on your property, with numerous plants, animal life and fish in the pond.

Type of Pond

Pre-formed Pond – A preformed pond liner is one of the easiest ways to get started in the hobby. They come in a variety of pre-formed shapes, are extremely durable and simple to install. They are also sold at most garden centers and are available for low prices online.

The downside of pre-formed ponds is that you are generally limited to only small sizes, and if you live in a harsh northern climate like I do, few are deep enough to allow fish to over winter. Pre-formed ponds will usually freeze completely in the winter and will kill any fish in them.

Pond Liner – Pond liners take a bit more work, but really let you design the pond how you want. They allow complete freedom when it comes to the size, shape and depth of a pond.

The downside is that they do take a fair bit of work to set up. You have to be very careful during set up, and they usually need a base of sand to protect against rocks, roots and anything else that can damage the lining.  You will also have to excavate a tiered hole to ensure that there are shelves for any plants that you want to put in.

One of the best places to buy low price pond liners is at Amazon.com.

Pond Pumps

Just like any body of water, if your pond doesn’t have any circulation it will quickly become stagnant. And stagnant ponds are not what exactly what you would call a good environment for plants and fish. But there is a simple way to provide circulation to a pond, and that is with a pond pump.

Before choosing a pump, you first need to decide what it’s going to be required to run. Is it just going to be a basic pump for circulating water, or will it also be used for a fountain, waterfall or a filter? Once you have decided what you are going to have in your pond, you should then move on to choosing a type of pump.

As a general rule of thumb, a pump should circulate all of the water in a pond at least once every two hours. So for example, if you have a 1500 gallon pond, you want to get a pump with at least a 750 GPH flow. Of course this number goes up drastically if you have a waterfall, unless of course you want it to be nothing more than an anemic trickle.

If you need help figuring out the size of your pond you can use the following formula.

Imperial – Length x Width x Depth x 7.5 = Approximate gallons in a pond

Metric – Length x Width x Depth /1000 = Approximate litres in a pond

Filters

While some ponds can get away with only having a pump, if you plan on keeping fish in your pond, a filter is an absolute must. The filter helps to remove impurities and debris from the water, and if properly maintained will prevent the water from becoming toxic to fish.

Most filters provide both biological and mechanical filtration. Mechanical filtration is simply the process of removing particles from the water (fish waste, algae, uneaten food). This helps to prevent the water from becoming cloudy over time, and the removal of these particles also prevents the water from fouling. It’s important to clean out the filter at least once a month to prevent detritus from accumulating and leeching back into the water.

Biological filtration is a bit more involved, and to put it simply is the breakdown of waste by beneficial bacteria in the filter. These bacteria grow slowly over time on a filter’s media, and breakdown the fish waste from ammonia, into nitrites, and then to relatively harmless nitrates – which are then used by the plants in the pond as fertilizer.

It’s important to understand that not all nitrates will be taken up by the plants as fertilizer, so in smaller ponds it’s important to do water changes regularly. For a water change, simply remove about 10-20% of the water in the pond, and replace it with fresh water that has been treated to remove any chlorine.

Some filters also provide chemical filtration, which works in conjunction with mechanical filtration. No chemicals are generally involved with this type of filtration, and the most common type of chemical filtration is the use of charcoal to remove impurities from the water. This type of filtration is less important than the other two, and not all filters will include this.

Plants

The addition of plants is vital to the health of the pond, and no pond looks complete without the addition of at least a few plants. There are several types of plants to choose from, and they are grouped into four classes.

Marginal or Bog – These are the plants that grow in shallow water or the saturated soil around the pond (cattails, irises).

Deep Water – These plants are planted in the deeper water of the pond, and will either emerge from the water, or will send shoots to the surface of the water (water lillies, lotus).

Floating – These plants are not rooted at all and will generally float on the surface of the pond (water lettuce, hyacinths)

Submerged -These are perhaps the most important plants if you are stocking the pond with fish, as they help to oxygenate the water. They grow completely underwater and many have to be weighed down to keep them in place until they root (cabomba, hornwort).

Pond Fish

Depending on your climate, there are numerous choices to stock a pond with. Some people prefer to stock the ponds with native fish, while others choose to stick with the more classic pond fish. No matter what you choose, fish are an excellent addition to nearly any pond, and more importantly, they will eat any mosquito larvae in the pond.

Goldfish – By far the most popular pond fish, goldfish are a hardy and attractive fish that can survive in all but the coldest climates. They are simple to care for, and can grow extremely large in a pond – with some even reaching 18 inches (46 cm) in length.

Because of their large size, you should ensure that they are provided with adequate space, and a good rule of thumb of is to provide 1 gallon (4 litres) for each inch of fish. Of course that doesn’t mean that one 12 inch goldfish only needs 12 gallons of water, as it still needs room to swim. But it’s a good starting point when stocking a pond with goldfish.

Koi – Koi are nearly as popular as goldfish, and they come in a stunning variety of colours. Before purchasing koi, it’s important to realize that they grow far larger than goldfish, and it’s not unusual to for a koi to reach 3 feet (0.91 metres) in length.

Because of their enormous adult size, they should only be kept in the largest of backyard ponds, and if you are just starting out, you should try goldfish first (especially since goldfish are 1/100 the price of koi).

Mosquitofish – These are mainly used in smaller ponds to help control mosquitos and have an unremarkable dull brown coloration. They stay relatively small in ponds, only growing to about 2 ½ inches (6 cm) and are live-bearers like guppies. Because they are live-bearers, you should be prepared for a population explosion and don’t be surprised if they quickly overrun a pond.

Rosy Red Minnows – These are another option for smaller ponds, and are far more attractive option than mosquitofish for mosquito control. They are also far more interesting, with males staking out a breeding territory and trying to entice females in. They will survive in a pond during the winter months as long as the pond doesn’t freeze solid.