Koi are domesticated versions of the carp and cousins of the goldfish. These brightly colored fish are right at home in a backyard pond or water garden. When building a diy koi fish pond, bear in mind that koi live for many years and size of their home will determine how large they grow. Also provide shade in a diy koi pond because these fish are easily burned by the sun and need a shady location to escape from direct sunlight during the heat of the day. Under the right growing conditions, this domesticated fish species can live to be 200 years old and reach a length of three feet. As a domesticated fish, koi will learn to recognize their owners and can be trained to eat from the owner’s hand. The colorful fish also has a few natural enemies and protection from raccoons, dogs, cats, snakes and large birds of prey should be consider when building a DIY koi pond.

Related: Diy aquarium stand, diy pond filter and diy fish tank ideas.

1- Pre-Made Koi Fish Pond

Use these step-by-step pictured instructions for constructing a DIY koi pond that will compliment the surrounding landscape. The addition of fake rocks and aquatic plant life make this pre-made pond look like it was there all the time.

2- Backyard Waterfall

Here is a relaxing idea for building a backyard garden pond. Detailed instructions show you how to build this pond with a waterfall that will offer beauty, relaxing sound and become home to colorful koi fish.

3- Waterfall Koi Pond

Transform a boring backyard space into an exciting water feature with this cool DIY koi pond idea. This is a large homemade fish pond with 4,000 gallons of water for fish to swim in and a waterfall.

This pond is raised above the ground and surrounded by a stone wall that is perfect for placing containers of plants. Add a light so the koi can be watched at night and place some comfortable seating around the pond and you create a private outdoor oasis.

4- DIY Backyard Pond Idea

This is one of the largest scale diy koi pond ideas that is on point if you want to have several fish in your backyard pond. When lots of koi are desired, a large pond is needed to prevent the build-up of ammonia in the water. Koi naturally release ammonia and when a lot of fish are in too small of a space, the ammonia builds up in the water and can kill the koi. See also diy pond filter to keep water clean.

5- Rock and Water Garden

DIY koi pond construction can also include other surrounding elements, such as a rock garden, to enhance the above ground view of the pond. While the koi are the main attraction of the pond, something above the water level should entice visitors to come and have a look.

6- DIY Koi Pond

How to build a koi fish pond that meanders through your backyard is detailed on this website. Long and winding, complete with waterfall, rock sides and colorful flowers, this is a perfect koi fish pond idea for a larger backyard.

7- Above Ground Koi Pond

Small, above ground and easy to build with these detailed instructions for a DIY build. This simple design allows the above ground koi pond and all its pump components to blend in with a tropical theme backyard garden with ease.

8- Custom Concrete Koi Pond

This is a great idea for anyone who lives in a house with a small front yard that connects to a busy sidewalk. It’s a koi fish pond that provides beauty and separation between your home and the rest of the world.

Constructed from concrete, this DIY fish pond is easy to customize to fit your exact outdoor space. Incorporate a sitting area, garden walls, steps, or other things that will make your small front yard an oasis.

Add containers of colorful flowers to add a pop of color and increase the curb appeal of your home.

9- Modern Koi Pond

This cool DIY koi pond is a modern design and will fit in perfectly with a minimal, modern backyard plan.

This free video contains detailed instructions that will show you how to build a koi pond on a budget. This koi fish pond can be customized to fit the backyard space and the design include a waterfall.

10- Cement DIY Koi Pond

Watch this YouTube video for a cool DIY koi pond idea. This organic-shaped koi pond is ideal for small spaces and is inexpensive to build. The shape of the fish pond can be designed to fit whatever outdoor space you have.

This DIY project can be built in a day, then allowed to dry and filled with water and fish. Add a few aquatic plants and you will have a lovely outdoor fish pond. This is a cool idea to build near an entranceway to increase the curb appeal of your home.

11- Low Maintenance Koi Pond

Follow the instructions in this YouTube video to create your own low maintenance koi pond. The two-step design allows space for aquatic plants to live in the water with the fish so you can enjoy fish and a water garden.

Beautiful rock design keeps the pond weed-free and creates an organic look that makes the pond appear to be natural instead of man-made. Ideal for a homestead with a rustic, natural look on the exterior.

12- Lighted DIY Koi Pond

How about building a koi pond that is the focal point in the landscape both day and night? This koi fish pond has a small waterfall and is lighted so the fish and scenery can be viewed day and night. Use solar lights so they won’t increase your utility bill or use natural resources.

Follow these step by step directions to discover how to transform a barren piece of property into an attractive lighted koi pond. Learn tips for designing and digging out dirt, plus tips for laying rock and installing lights with this cool idea.

13- Window-Side Koi Pond

This cool idea shows you how to make a koi pond just outside of your home so it can be viewed through the window while you are inside the home.

After a long day at work, it’s relaxing to come home and watch the fish swim around from the air-conditioned comfort of your home. No matter what the weather is outside, you can still watch the koi from the inside if the DIY pond is located just outside by a window.

Add solar lights around the DIY koi pond so you can enjoy watching the fish after dark. The solar lights will also double as outdoor night lights and solar power is eco-friendly and free.

14- Affordable Backyard Koi Pond

Watch this YouTube video for a cool idea for building an affordable DIY koi pond. The build is quick and easy and can be completed in one day. The shape and size in the YouTube video are easy to customize to fit your space.

This cool design uses the oblong shape of the blue plastic liner to save money and time on the DIY project. This DIY project will cost less than $50 so it won’t break the budget.

15- Water Garden and Koi Pond Combo

Here’s a cool idea that will show you how to have two things in one outdoor space. Follow these instructions to make a koi pond and a water garden in a raised bed in the backyard.

Build a frame, create a koi pond in the center, fill the remaining space with soil, and now add the decorative items. Fill the pond with water and koi, create a waterfall, and plant flowers around the perimeter.

It’s a raised bed water garden and koi pond combo that can be created to fit your outdoor space. Since the plants are not in the water but in the soil that fills in the area around the DIY koi pond, you can plant and grow vegetables, fruits, flowers, or herbs in the space.

16- Wood Frame Koi Pond

Start with a wood frame, then add what you want to make a DIY koi pond. This YouTube video shows you how to construct a basic wood frame that will become the beginning of your fish pond.

Leaves the wood frame above ground, or dig down into the soil so some, or all of it, will be flush with the top of soil. Easy to design and customize to fit any outdoor space, the wood frame is inexpensive and quick to build.

Add a liner inside of the wood frame to keep the water and fish securely inside and that’s all there is to this DIY project. However, you can add paint, rocks, or any other design elements to the exterior or the top edges to transform a simple wood frame into a work of art.

17- Corner Koi Fish Pond

Small and attractive, this mini pond idea is perfect for a small courtyard. Great for those who own condos and would like an outdoor water feature and unique pets that require very little care. This corner fish pond idea shows how to build an above ground koi pond that not only provides visual interest to a small courtyard, but also provides additional outdoor seating.

https://www.youtube.com/watch?v=rB0JAhg0u4M