How to Make a Mini Outdoor Pond for Aquarium Fish

Everybody is ready to take a walk outside as soon as the weather gets warmer. 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. In times of drought, your pond may become a vital part of the local ecosystem.

How can you create a mini-pond?

Finding a

container

It is one of the most straightforward parts of making your 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. Metal containers may not be ideal for holding shrimp or snails. Invertebrates can be more sensitive to trace elements in the water.

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

Temperature management can be affected by the location of your container. 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. The earth will also help the mini-pond to stay cool in the summer and warm in the winter. Another option is to bury it in the ground. 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. An important step is to protect the electrical equipment from sun and rain. A garage can be used to protect the air pump and allow the mini tub to run outside. If this is not possible, get a weatherproof connection box from the hardware store to protect any power cords and extension cables. To reduce UV damage, you’ll need to cover your air pump inside a weatherproof container or under an upside-down bag.

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 to Use in a Small Pond?

Because of their many benefits, we recommend that you include aquatic plants in your pond. 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

Other plants for your pond include duckweed, water lettuce, water lilies, lotuses, and even aquarium plants. Toss in some water sprite or other stem plant trimmings, and they will flourish and multiply under the natural sunlight. The power of plants means that there is no need to worry about fallen leaves, branches, and other decaying materials 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

Multiple species can be kept together as long as they are peaceful and don’t eat one another. 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. Raccoons, cats, and larger birds will happily eat whatever you give them. 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.) For perennial plants that will come back next year, cut back their leaves to begin their dormant period and store them in the garage or underneath the overturned pond container.

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 are warmer in winter, but need extra safety fencing to protect pets and children.

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