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? Your mini pond will usually last between May and September in a climate with distinct seasonal changes. 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 drought times, your pond can become a vital component of the local eco-system.

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. To reduce temperature swings and water quality problems, it is better to use larger containers. 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 can become beautiful mini ponds for your backyard or apartment balcony.

The location of your container can play a significant role in temperature management. You can place your container under the shade, if possible. As the temperature doesn’t change so much, less algae will grow. (Algae is good for your fish, but it may not be as desirable if you plan on growing plants for profit.) Shade cloths can be used to reduce the amount of sun that hits your container if there isn’t enough shade. Another tactic is to bury the container partially or entirely in the ground since the earth will help the mini pond stay cooler in the summer and warmer in the 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. Protecting the electrical equipment from rain and sun is an important step. A garage can be used to protect the air pump and allow the mini tub to run outside. To protect power cords or extension cables, you can get a weatherproof connector box at your hardware store. 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 replace the evaporation in the mini pond. However, you might need to add water to the container with the hose if it is in 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?

A variety of benefits that aquatic plants provide are why we highly recommend them for 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. Add some water sprite, or other stem plant trimmings to your pond and they will thrive and multiply in 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

You can even put multiple species together, as long as they’re all peaceful and won’t eat each other. 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 can 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. There’s no foolproof protection, but here are some methods to try, depending on which animals you’re having trouble 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. People put “lids” over their tubs, such as metal wire racks or greenhouse siding. These allow light through but keep 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 can you winterize small ponds?

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 keep it warmer in winter but require extra protections such as safety fences to keep small children away.

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