How to Make a Mini Outdoor Pond for Aquarium Fish

When the weather warms up and summer is upon us, everyone is itching to go outside. What better way to enjoy nature than to set up your first mini pond for breeding aquarium fish? If you live in a temperate climate that experiences distinct seasonal changes, then your mini pond fun usually lasts for 3 to 4 months in the summer (e.g., sometime between May and September in the United States). However, if you live in the subtropical zone that stays above 50degF or 10degC for most of the year (like Florida), then you can play with fish outdoors all year round.

Nature does a spectacular job of raising fish in many ways, and we can learn some valuable lessons by putting our fish outside. Fish and shrimp develop brilliant coloration when grown under sunlight and fed natural foods like green water, algae, fallen leaves, and live insects. Mini ponds not only house an abundance of fish babies and plants for you to enjoy, but they also attract all sorts of wildlife – such as bugs, frogs, birds, and even deer. Your pond could become an important part of the local ecosystem during drought.

How do you make a mini pond?

Find a

Container

is one of the easiest parts of making a mini pond. You can start with something as ordinary as a 5-gallon bucket or purchase a giant 300-gallon plastic stock tub from a livestock feed store. Other ideas include old aquariums, kiddie pools, and half whiskey barrels. Larger containers are better for reducing temperature swings and water quality issues. Containers made of metal might not be suitable for shrimp and snails because invertebrates are more sensitive than others to trace metals in water.

Even large decorative pots could be used to create beautiful mini-ponds for your balcony or backyard.

The location of your container can play a significant role in temperature management. You can place your container under the shade, if possible. You will see less algae grow because the temperature won’t fluctuate as much. (Algae is good for your fish, but it may not be as desirable if you plan on growing plants for profit.) To reduce sun exposure, shade cloths are a good option if the container is not in a strong enough shadow. You can also bury the container in the ground, either partially or completely. This will keep the mini pond cooler in summer and warmer in winter. They do require safety fencing to protect small children and pets, just like an inground pool.

When it comes to filtration, a simple sponge filter with an air pump should suffice for a mini pond, but you can also buy a pond filter or make your own DIY bucket filter for keeping larger fish like goldfish and African cichlids. It is important to shield the electrical equipment against rain and sunlight. You can shelter the air pump in a garage, and then run the airline tubing outside to the tub. To protect power cords or extension cables, you can get a weatherproof connector box at your hardware store. You’ll also need to cover the air pump itself inside a weatherproof box or underneath an upside-down tote to decrease UV damage.

Once the equipment is set up, fill the container and add dechlorinater to make the tap water safe for fish. Rain should be able to replace evaporation, but it may be necessary to fill the container with water hoses if the area is experiencing drought. In the rest of the article, we’ll talk about plants, fish, and predator deterrents to add to the mini pond.

What are the best plants for small ponds?

We highly recommend adding aquatic plants into your pond because of the many benefits they provide. Plants offer shade and shelter for fish to hide from predators, as well as landing spots for insects and amphibians to take a drink. Because of its stunning purple flowers and long bushy roots, water hyacinths are a favorite pond plant. They provide excellent cover for fish. Water treatment plants often use them because of their amazing ability to draw out organic waste from the water and remove toxins.

Water Hyacinth in Bloom

Water lettuce, duckweed and lotuses are all good options for your pond. You can also add water sprite and other stem plant trimmings and your plants will grow and flourish in natural sunlight. Because of the power of plants, there’s no need to worry about any fallen leaves, branches, or other decaying matter in the container. The plants purify the water, and your mini ecosystem (consisting of algae, microorganisms, and fish) helps break them down.

What Fish Can You Put in a Small Pond?

This question requires some additional research on your part in terms of how long certain fish can stay outside in your climate zone, but we’ve found great success with these hardy species, some of which can tolerate cooler temperatures:

– Variatus platies – Wild type endlers – Cherry shrimp – Ricefish – White cloud mountain minnows – Killifish – Japanese trapdoor snails – Koi and goldfish – Apistogramma dwarf cichlids – Rainbowfish

Multispecies can be combined, provided they’re peaceful and don’t eat each others. Most fish breed readily outside, so make sure to have an exit strategy in terms of where to keep all the babies. Selling the extra fish and plants to friends, fish stores, or online auctions at the end of pond season can be a nice way to recoup some of your summer tubbing costs.

Livebearers are a common fish to breed during pond season because of their healthy appetites and high birth rates.

How Do You Protect Your Pond From Predators?

Unfortunately, by putting little fish out in nature, you’re also providing potential food for the local wildlife. Cats, raccoons, and larger birds are happy to get a free meal wherever they can. If you don’t have any bigger fish in the mini pond, dragonfly larvae can find a way to sneak in and catch some baby fish. You can’t guarantee protection but there are ways to protect the animals you have problems with.

The first line of defense is to provide plenty of hiding spots for the fish using plants, PVC pipes, plant shelves, hardscape, and other decor. Some people put “lids” on top of their tubs (e.g., metal wire racks or greenhouse siding) that still allow light to pass through while keeping predators out. Others prefer to use netting, a grid of clear fishing line, or mesh covers that can be easily removed for your enjoyment.

If you see a strange alien swimming in your pond, it might be a dragonfly larva predating on fish fry.

How do you winterize a small pond?

Most tropical fish cannot live outdoors during the winter seasons, so drain the water and bring them indoors when temperatures start dipping below 65degF or 18degC. (If you want to keep the fish out longer, consider using a heater to add an extra month of pond season in the spring and fall.) If you want perennial plants to return next year, trim their leaves to start their dormant periods. Then store them in the garage.

If you want to try keeping cold water fish outdoors in the winter, use a small air stone or sponge filter to keep the water somewhat aerated and allow sufficient oxygen to reach the fish. If the tub is large enough or buried inground, stratification may occur, such that the surface ices over and insulates the warmer water at the bottom where the fish are “hibernating.” Smaller containers with fish can be moved entirely into the garage to decrease the chances of freezing.

Inground ponds stay warmer in the winter but require extra precautions like safety fences to keep out small children and pets.

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