How to Create a Beautiful Waterproof Pond in Your Backyard

A backyard pond water feature

Thinking of installing a backyard pond but not sure where to start? From picking the right sized pond, to finding the right waterproofing solution and figuring out how to keep fish alive, this handy guide has everything you need to start your journey to building the perfect pond.

Choosing the right location

Before you even commence designing and building a pond, you first need a location. And just like building a house, location is everything. Here’s some handy hints from Aquarium Tidings on selecting the perfect spot for your beautiful backyard water feature.

  1. Avoid trees: While a leafy aspect with bowed branches hanging over your pond might seem idyllic, it’s actually going to be more trouble than it’s worth. Leaves falling during autumn will cover and choke your pond, leading to near constant maintenance. Decaying leaves left in water will cause a rise in ammonia levels, which can be dangerous to fish and other marine life in your pond.
  2. Try to keep it level: Unless you’re feeling ambitious (or just have a bunch of money to burn) a flat, even location for your pond is going to be easier to construct and waterproof.
  3. Half shade and half sun: To avoid heavy growth of algae and promote healthy conditions for your watery inhabitants, it’s beneficial to place your pond in a spot where it will receive direct sunlight for about half the day. Too much sunlight will see a rise algae – not enough will stifle fish and plant life in water. Getting the balance right can be tricky, and when you want to avoid using too much tree cover, but think creatively and you’ll usually find a solution. The house, nearby elevations or even a purpose built screen can all help manage sun exposure to your pond.
  4. Check with council: Before starting, you’ll want to check with council and make sure that what you intend to do with your pond is all above code and that there’s no infrastructure lying in the ground. Accidentally unearthing power lines can lead to injury and even death.

How to choose the right size for your pond

Location, budget and property size restrictions will affect how large your pond can be. The size of your pond will also determine the types of flora and fauna you can have successfully living in the pond, as well as ongoing costs and the effort of maintenance. Here’s a breakdown for the three main categories in backyard and home ponds.

Small ponds – 40 to 200 litres

Starting small let’s you learn how to manage a home pond without too much stress or maintenance. You’ll get to design, create and waterproof your pond on a modest budget and see it come to life.

Plant life in small ponds is limited to marginal and bog varieties with the occasional submerged plant to help oxygenate the water. Rosy red Minnows and mosquitofish are a good starting point for small ponds, whereas Koi and goldfish require too much space for the tight confines of a smaller water feature.

Medium sized ponds – 200 to 4,000 litres

With such a wide range in volume, medium sized ponds come in a versatile range of shapes and sizes, and are common among backyard pond owners who already have some experience in maintaining a pond.

Filtration is more of an issue with medium sized ponds. You’ll need to think carefully about where you place the filter to avoid clogging and ensure it can successfully pump water throughout the pond. With careful planning, however, you can scale a lot of maintenance needs so that owning a medium sized pond isn’t too much more difficult than looking after a smaller pond.

Pond waterproofing at this size is a bit more challenging. Using a complete and highly durable system, such as the Wolfin and Cosmofin waterproofing membranes, as well as a professional installer, will go a long way to ensuring your pond retains its waterproof status for a long time.

Large ponds – 4000 litres and up

There’s really no limit to how big you can make your pond, and once you’ve mastered smaller sized ponds, you’ll be better positioned to make good decisions in planning and building your future pond projects.

Keep in mind that considerations like waterproofing the pond at this scale require careful planning, knowledge and skill. You won’t want to skimp on systems or materials, as large, poorly waterproofed ponds can be a nightmare to maintain, not to mention the effects on your surrounding property. Again, Projex’s Cosmofin and Wolfin PVC waterproofing systems are the perfect solution to keeping your pond water-tight.

Choosing your fish

There are several types of fish that are a beautiful, natural fit to ponds, and that will happily thrive if you take proper care of them.


Popular, expensive and growing quite large in size, koi are suitable for larger ponds only. Keeping koi is best attempted by folks who are already experienced with backyard ponds.


By far the most popular kind of fish in ponds, goldfish can grow quite large and are great survivors. You’ll need to ensure they have enough space to swim around in. Small ponds are not suitable for these type of fish, but medium and up should be fine.


Small and generally dull, mosquitofish are useful as they keep the mosquito population at bay around your pond. However mosquitofish have population issues of their own. As live-bearing fish, you may experience the occasional population explosion that can overrun your pond.

Rosy Red Minnows

Suitable for small ponds, the rosy red is more attractive than the mosquitofish but will also help control mosquitos. Rosy Red’s also exhibit interesting mating characteristics, with the males staking out territory and enticing females.

Waterproof with high quality materials

Essential to the success of your backyard pond is a waterproofing system that is:

  • Will last the lifetime of your backyard pond
  • UV stable
  • Resistant to plant root growth.

Pond waterproofing is performed by a waterproofing contractor, so you’ll want a product that is preferred by tradespeople.

Developed in Germany, Wolfin Membrane Systems have over 50 years experience formulating waterproofing system worldwide. They offer a complete pond waterproofing solution that is suitable for most pond sizes and shapes.

Wolfin and Cosmofin membranes are designed and manufactured to integrate all the components into the membrane, ensuring total compatibility with:

  • Factory bonded steel profiles
  • Bonding adhesive
  • Absorbent and nonabsorbent substrates
  • Universal pins for securing directly to the Cosmofin or Wolfin membranes without piercing the membrane.

You wouldn’t cut corners when building your home, so why risk damaging your house and undoing your hard work by choosing substandard waterproofing products? Select top grade waterproofing and future proof your pond for years to come. Not sure if the pond the right water feature? Check out our guide on choosing the right feature for your home.