If you’re serious about the prospect of building a backyard pond, then you probably already know that there is a lot more to this fulfilling hobby than just digging a hole and filling it with water. But, do you know the difference between a mag drive pump and a direct drive pump? How about EPDM pond liner vs. polypropylene? Don’t worry; we didn’t either, which is why we drove out to Vandermeer Nursery in Ajax, Ontario to speak with water features expert, Terri John.
Before you dig
When it comes to getting started, Terri advises that it’s absolutely necessary to do your homework. Of course, one of the best resources on building a backyard pond is your local pond supply specialist, such as the ponding department at Vandermeer Nursery.
“If you have friends who have ponds, speak to them and go look at [their ponds],” Terri says. “[Also], go online to research what kind of water feature you want,” she says. “You really have to pick and choose what you feel is right for [your needs], so you don’t end up filling it in a year or two later.”
In terms of whether you should create the pond on your own or hire a contractor to do the work for you, the decision should really be based on how comfortable you are and just how much work you’re willing to do upfront.
If you do decide to hire a contractor, as always, be sure to choose a reputable, experienced professional.
“If you’re investigating contractors to [build your pond], then you definitely need to go and look at [the contractor’s website],” Terri advises.
She also notes that a reputable contractor will know that a pond deeper than 24 inches requires a permit. This is important, because anything less than that is fine if you’re only planning a water garden. However, if you want to keep fish in your pond, then a depth of 24 inches can mean that you’ll have to bring the fish inside over winter or else risk fish death.
As mentioned in our first post, be sure to check with your municipality before you dig.
“A lot of municipalities treat [ponds] like pools,” Terri says.”So they must be fenced within a fence.”
Essential Pond Equipment
There are three essential pieces of pond equipment required to get started with your build: the pond liner, a good pump, and a filter. If you’re planning to add fish to your pond, then you’ll want to add aeration, and then a pond de-icer for overwintering (we’ll touch more this in part 3 of this series).
Let’s take a look at the essential components.
There are three categories of water retention materials: rolls (EPDM and PVC), preforms (polypropylene and fiberglass inserts), and spray-in (rubber and waterproofed concrete).
There are several reasons why someone might select one type of liner over another, with cost being a primary factor. In addition to that, some people might gravitate toward a preformed pond liner due to the visual cues that it offers.
The downside to using a preform is that they are available in a limited number of shapes, sizes and depths. However, if you only want a small water garden or in-deck feature, then a preform might be the right option.
Keep in mind that a preform is not the best option for someone who wants to add fish to their pond. They tend to be too small and too shallow for overwintering fish. They will also make it much easier for predators to make a meal out of your fish.
By contrast EPDM rubber liners (which come as a sheet) provide nearly limitless flexibility. This type of liner means that your pond can be any shape, size or depth, making it the preferred liner option among pond owners who keep koi or larger goldfish.
Terri warns that, while preformed liners may appear easier to install, the truth is that their installation is actually more difficult.
“When it comes to installation with a preform you need to be extremely level and you need to have a proper compact base,” she says. “If you’re not at level, the water is going to tell you and [your pond] can end up looking odd. Then if it gets too full it’s going to drain out”.
Your choice of water pump depends upon what you intend to do with your water feature. Pumps need to be matched to the size of the pond, the filter, extra features, and the function of the pond. The bigger your system, the more volume you need in order to run it.
If you aren’t planning to keep fish in your pond, then ½ gallon per hour per gallon of pond should be sufficient. Keep in mind, however, that this is not so where fish are concerned. In a fish pond, the rule is at least 1 gallon per hour per gallon of pond.
“When a pump says 42 hundred gallons an hour on the box, it’s only that at maybe 1 or 2 feet,” Terri warns. “Depending on whether you’re using a mag drive pump or direct drive pump, as soon as you go past [1 or 2 feet], you’re going to need more”.
Here are some additional details about the the two most popular types of pond pumps.
Magnetic (mag) Drive Pump – This type of pump is powered by an electromagnet that drives an impeller and magnetic shaft. The magnetic shaft and impeller spin in the magnetic field created by the electromagnet to push water through the outlet of the pump. It is this method of pumping the water out that makes mag pumps more energy efficient than other comparable pumps.
Direct Drive Pump – In direct drive pumps, a motor physically turns a shaft and impeller. The use of electricity to directly power this mechanism can lead to higher energy consumption than with a mag pump.
According to Terri, there is also a difference in how easy or difficult they are to maintain.
“Direct drive pumps can’t really be maintained without taking them to a pump specialist, whereas a mag drive pump is pretty user friendly,” she explains. “If [a mag drive] breaks, the impellers are replaceable. If you break an impeller in a direct drive, you’re done.”
When it comes to pond filtration, you can never have too much. However, too little filtration can cause considerable problems. Keep in mind that filters are generally rated for ponds without fish. If you do plan to have fish in your pond, then you’ll need to cut the filter’s rating in half.
There are three basic types of pond filtration systems: Skimmer/waterfall external filtration, submersible filtration, and external filtration.
Skimmer Filtration (external) – this type of filter skims debris from the surface of your pond. A pump at the bottom of the skimmer directs water to the opposite side of the pond, where it cascades back in, often through a waterfall. It can also act as a secondary mechanical filtration system.
“A lot of people overlook skimmer filtration,” Terri says. “It’s an important component of any pond, whether it’s a water garden, fish pond or ‘bogs and frogs’”.
Submersible Pond Filtration – A submersible filtration system places a pump at the bottom of your pond. There, suction draws water through the filter and then pushes it out to a fountain or waterfall.
External Pond Filtration –Absolutely indispensable in a pond with fish, an external filtration system draws water from your pond to a canister filter that sits outside of the pond at a higher elevation. Filtered water then pours out of the filter plumbing and can be directed over a waterfall or streambed.
There are also bottom drain filters, which are generally used in ponds with fish, especially koi.
Aeration is generally not needed in water gardening, but is very important for fish or amphibians.
“Aeration adds a lot of circulation that you won’t get from waterfall or fountain,” Terri says. “It circulates water to the surface much faster than a pump could”.
You keep your oxygen level high, so the water starts to “clean itself” in a lot of ways. You can put it next to the pump to help keep the pond even cleaner.
Of course, to get a real understanding of the different types of liners, pumps, filters and other aspects of creating your perfect pond, your best option is to gather all of the information about the pond you’re trying to build and go in to speak with a pond specialist, like Terri John over at Vandermeer Nursery.
Be sure to check back next week for our third and final part to our series on installing a backyard pond. In this final installment, we will discuss adding plants and fish to your pond, as well as pond maintenance and overwintering.
If you missed our first installment in this series on building a backyard pond, you can read it here.
Vandermeer nursery has served Ajax and the Durham Region for over 40 years, providing high quality, 98% locally grown plants, gardening supplies and accessories, ponding equipment, fish and more to the Greater Toronto Area.