Koi Aren't Your Only Option: 8 Pond Fish and the Type of Pond Each One Needs

by Tory Jon | Last Updated: July 19, 2026

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Koi may get most of the attention, but they are not the only fish worth considering for a pond.

Colorful goldfish varieties can be a better fit for a lined backyard water garden, while bluegill, bass, catfish, and other species may work in larger earthen ponds. Some fish are stocked for their appearance, some for fishing, and others to serve a specific management purpose.

That does not mean all eight fish on this list belong together. A small ornamental pond beside your patio is very different from a half-acre fishing pond, and the fish that thrive in one may be completely inappropriate for the other.

This guide explains what each fish can offer and, more importantly, the type of pond it actually needs.

Shubunkin Goldfish (Carassius auratus)

Best pond type: A lined ornamental pond or water garden.

Shubunkins are one of the most colorful alternatives to koi. Their calico patterns may include blue, black, orange, red, yellow, and white, with no two fish looking exactly alike.

Most shubunkins have the same long, streamlined body found on common and comet goldfish. This makes them stronger swimmers than fancy goldfish with extremely rounded bodies, oversized fins, or bulging eyes.

Oklahoma State University Extension includes shubunkins, comets, common goldfish, and fantails among the goldfish varieties used in water gardens. It recommends choosing fish with relatively normal body shapes for outdoor ponds.

Shubunkins can live with other active goldfish varieties, including comets and Sarasa comets. They should not be crowded into a small water feature simply because they are small when purchased. They grow, reproduce, and produce more waste as they mature.

Their bright coloring also makes them easier for herons, raccoons, cats, and other predators to spot. Pond plants, shaded hiding areas, caves, and pond netting can offer added protection.

Sarasa Comet Goldfish (Carassius auratus)

Best pond type: A lined ornamental pond with open swimming room.

Sarasa comets are known for their red-and-white coloring. When seen from above, a well-marked Sarasa may look somewhat like a small red-and-white koi.

One easy way to distinguish the two is to look near the mouth. Koi have small whisker-like barbels, while goldfish do not.

Sarasa comets have long bodies and single tails. They are fast, active swimmers and usually compete well for food alongside common goldfish and shubunkins.

Slower fancy goldfish may struggle in the same pond because the comets can reach food first. Fish with similar swimming abilities are generally easier to manage together.

Sarasa comets are omnivores. They may eat prepared pond food, algae, plant material, insects, and small invertebrates. Although they may eat some mosquito larvae, fish alone cannot correct every mosquito problem in a pond.

Fathead Minnow (Pimephales promelas)

Best pond type: A new earthen fishing pond that needs an initial forage fish population.

Fathead minnows are small fish commonly stocked as food for young bass and other predatory fish. Adults generally remain small enough to be swallowed by juvenile game fish.

They reproduce by attaching eggs to the underside of rocks, boards, plants, and other submerged objects. Male fathead minnows guard the eggs until they hatch.

Their ability to reproduce quickly can help establish a food source before predators are introduced. However, they should not be expected to remain abundant after a pond is stocked with bass.

The Missouri Department of Conservation describes fathead minnows as ideal forage fish because adults are usually small enough to be eaten by juvenile predators.

Fathead minnows are sometimes placed in small ornamental ponds, but larger goldfish may eat their eggs or young. Bass, bluegill, and other predatory fish can consume the adults.

Purchase minnows from a reputable hatchery rather than moving baitfish or wild minnows from another body of water. Transferred fish can introduce diseases, parasites, or unwanted species, and moving live fish may violate local regulations.

Bluegill (Lepomis macrochirus)

Best pond type: A larger earthen fishing pond managed with predator fish.

Bluegill are among the most commonly stocked fish in private fishing ponds. They feed on insects, small aquatic animals, zooplankton, and other natural food found in the water.

Bluegill also reproduce readily. That makes them a valuable food source for largemouth bass, but it can create an overcrowded population when a pond does not contain enough predators.

An overcrowded bluegill population may contain large numbers of undersized fish competing for limited food. Adding a handful of bluegill to an unmanaged backyard pond is not the same as establishing a balanced fishery.

The Kentucky Department of Fish and Wildlife Resources recommends bluegill as part of a managed combination that commonly includes largemouth bass and, when desired, channel catfish. It also notes that managing several fish species becomes more difficult in smaller ponds.

Bluegill are not a good substitute for goldfish in a small lined water garden. They belong in an earthen pond with enough habitat and a stocking plan designed around the entire fish population.

Largemouth Bass (Micropterus salmoides)

Best pond type: A managed earthen fishing pond with an established prey population.

Largemouth bass are usually stocked as the main predator in a traditional bass-and-bluegill pond. They feed on bluegill, minnows, insects, crayfish, and other available prey.

The relationship between bass and bluegill helps keep both populations under control. Bluegill produce young fish for bass to eat, while bass reduce the number of bluegill competing for food.

That balance does not maintain itself automatically. Too many bass can lead to a pond filled with small, thin bass. Too few bass can allow bluegill to become overcrowded.

Harvesting decisions, water fertility, habitat, pond size, and the number of fish stocked can all affect the result. Local extension offices and state fisheries biologists can provide recommendations based on the region and the pond owner’s fishing goals.

Largemouth bass should not be added to an ornamental goldfish pond. They are predators and may consume goldfish, minnows, frogs, and nearly any other animal they can swallow.

Redear Sunfish (Lepomis microlophus)

Best pond type: A warm-water earthen fishing pond stocked as part of a larger management plan.

Redear sunfish are often called shellcrackers because they feed heavily on snails, clams, and other hard-shelled aquatic animals. They also eat insects and other small organisms found near the pond bottom.

They are sometimes stocked alongside bluegill to add another type of panfish to the pond. Redear generally do not reproduce as heavily as bluegill, so they are usually treated as a supplement rather than the pond’s main forage fish.

Their appetite for snails has led to claims that redear sunfish prevent fish parasites. That goes too far. They may reduce some snail populations, but they should not be treated as a cure or guaranteed method of disease prevention.

Redear sunfish are better suited to warmer regions than areas with severe winters. Stocking recommendations differ by state because climate, growing season, and local fish communities vary.

Like bluegill, redear sunfish are not intended for a small decorative water garden. They belong in an earthen pond managed for fishing and a balanced fish population.

Channel Catfish (Ictalurus punctatus)

Best pond type: An earthen fishing pond, either as an additional sport fish or under a catfish-focused stocking plan.

Channel catfish are popular in private ponds because they provide another fishing opportunity and readily accept commercial floating feed.

They are omnivorous and may eat insects, crayfish, plant material, small fish, and prepared food. Despite their reputation as bottom feeders, channel catfish are not pond-cleaning machines. They produce waste just like every other fish.

Catfish can be added to a balanced bass-and-bluegill pond, but they are not needed to control either population. Their purpose is mainly to provide an additional fish for anglers.

University of Missouri Extension notes that channel catfish do not reproduce well in ponds containing bass. Harvested catfish may need to be replaced, and newly stocked fingerlings must be large enough to avoid being immediately eaten.

Channel catfish can also be raised in a pond managed primarily for catfish. That approach requires careful attention to feeding, water quality, aeration, and harvest.

Excess food should not be allowed to accumulate. Decomposing feed and fish waste can contribute to low oxygen, high ammonia, algae growth, and poor water quality.

Triploid Grass Carp (Ctenopharyngodon idella)

Best pond type: A larger earthen pond with a confirmed submerged vegetation problem.

Grass carp are not ornamental pond fish and should not be added simply because a pond has some plants or algae.

They are stocked as a biological control for certain types of aquatic vegetation. Grass carp prefer some plants over others, and they may ignore the exact weed a pond owner wants removed.

These fish are also not a dependable solution for filamentous or planktonic algae. Identifying the plant before stocking grass carp helps determine if the fish are likely to eat it.

Too many grass carp can remove most of a pond’s vegetation. That may eliminate habitat used by young fish, insects, amphibians, and other wildlife while also making the water more turbid.

Only functionally sterile triploid grass carp should be used where they are permitted. The U.S. Fish and Wildlife Service operates a certification program that allows states and buyers to confirm that grass carp supplied through participating producers are triploid.

State rules vary considerably. Some states require a permit, restrict the number that may be stocked, require barriers to prevent escape, or prohibit grass carp entirely.

Stocking recommendations also depend on the plant species, the amount of vegetation, the pond’s size, and the desired level of control. A generic fish-per-acre number should not be applied without first identifying the problem.

Which Fish Belong in an Ornamental Backyard Pond?

For a typical lined backyard pond or water garden, shubunkins and Sarasa comets are the two strongest choices on this list.

They add color and movement without reaching the potential size of koi. They still need adequate water volume, filtration, oxygen, and room to grow.

Goldfish reproduce readily, so even a lightly stocked pond can become crowded over time. Starting with fewer fish gives them room to mature and leaves capacity for unexpected offspring.

A good pond filter helps process fish waste, but filtration does not make unlimited stocking safe. More fish consume more oxygen and produce more ammonia.

Which Fish Belong in an Earthen Fishing Pond?

Bluegill, largemouth bass, redear sunfish, channel catfish, and fathead minnows are associated with larger earthen ponds rather than small decorative water gardens.

These fish should be selected as part of a complete stocking plan. Adding individual species without considering reproduction, predation, harvest, and available food can create an unbalanced population.

For example, fathead minnows may help establish an early food supply, but bass can consume them quickly. Bluegill reproduce heavily and need predators. Channel catfish may need to be restocked after harvest.

Pond size also affects the choices available. Small ponds are generally more difficult to manage as multi-species fisheries and may work better under a simpler stocking plan.

Can Ornamental and Game Fish Live Together?

Placing ornamental goldfish in a bass pond usually does not end well for the goldfish. Bass are predators and may eat any goldfish small enough to swallow.

Bluegill and other sunfish can also eat fish eggs and young goldfish. Larger game fish may stir up sediment, damage plants, or compete for food.

Goldfish may survive in some large earthen ponds, but they can reproduce, become invasive if they escape, and interfere with the pond’s management goals. They should not be released into natural waterways or public ponds.

The U.S. Fish and Wildlife Service advises owners to return unwanted fish to a pet store that accepts them or find another responsible owner rather than releasing them.

How Many Fish Should You Add?

No single stocking formula works for every pond.

An ornamental pond’s capacity depends on water volume, surface area, filtration, aeration, temperature, fish size, feeding, and maintenance. A pond that appears lightly stocked with young fish can become overcrowded as they grow.

Earthen pond recommendations are commonly based on surface acreage, regional growing conditions, water fertility, and the combination of fish being stocked. Rates developed for one state or pond-management goal may not work in another.

Before stocking a fishing pond, contact a local extension office, fisheries biologist, or licensed hatchery familiar with the area. They can help match the stocking plan to the pond and its intended use.

Tips for Adding Fish to Your Pond

Buy fish from a reputable hatchery or pond-fish seller. Avoid moving fish from another pond, lake, river, or bait bucket.

Inspect new fish before adding them. Fish with sores, white spots, damaged fins, poor balance, or unusual swimming behavior may be sick or badly stressed.

Do not immediately pour fish into water with a different temperature. Float the closed transport bag in a shaded area of the pond, then gradually introduce small amounts of pond water before transferring the fish.

A separate quarantine system can reduce the chance of introducing parasites or disease into an established ornamental pond.

Watch new fish closely during the following days. Gasping at the surface, rubbing against objects, refusing food, loss of balance, or visible sores can indicate a problem.

Check out this quick video for more tips on safely adding fish to your pond.