Koi & Pond Fish

Shop koi and pond fish for outdoor ponds, water gardens, and large freshwater setups. This collection features beautiful live pond fish like Assorted Koi and Butterfly Koi, along with the striking Chinese Highfin Shark and other unique species suited to spacious aquariums and pond environments. Koi and pond fish are active, colorful, and rewarding to keep, but they grow large and do best with plenty of space, strong filtration, and long-term planning. If you are also stocking an indoor tank, browse our wider freshwater fish and goldfish collection, since goldfish share the same cold-water care needs.

Featured Koi and Pond Fish

Our Assorted Koi offer the classic mix of colors and patterns that make koi keeping so rewarding, while Butterfly Koi add long, flowing finnage that looks spectacular gliding through a pond. For something truly different, the Chinese Highfin Shark is a peaceful, sail-finned oddball that grazes the bottom and becomes a real showpiece as it grows. All of these fish are cold-water species that thrive in cool, clean, well-oxygenated water, making them ideal for ponds and very large aquariums rather than warm tropical tanks. Seasonal pond fish are also added when available.

Pond and Tank Requirements

Koi, butterfly koi, and Chinese Highfin Sharks all grow large and need room to thrive. Outdoor ponds should offer plenty of volume and depth so water stays cool in summer and resists freezing solid in winter, while indoor keepers should choose the largest setup possible from our glass aquariums. Strong biological filtration is essential because pond fish are heavy eaters and produce a lot of waste, so pair your system with filtration from our aquarium filtration lineup rated above your water volume. Hardy live aquatic plants can help absorb nitrates and provide shade, though large koi may nibble softer varieties.

Water Quality and Care

Stable, high-quality water is the foundation of healthy pond fish. Keep ammonia and nitrite at zero and nitrate low through regular water changes, and always treat tap water with a quality water conditioner to remove chlorine and chloramine. Test your parameters regularly with a reliable test kit, and stay on top of routine upkeep with our aquarium maintenance supplies. For a deeper walkthrough, see our Koi Care Guide and Chinese Highfin Shark Care Guide, which cover seasonal care, feeding, and health in detail.

Feeding Koi and Pond Fish

Koi and pond fish are omnivores with hearty appetites. Feed a high-quality floating pellet formulated for koi or pond fish, and offer bottom-grazing species like the Chinese Highfin Shark sinking wafers that reach the substrate. Browse our full aquarium fish food selection for color-enhancing and seasonal diets, and remember to feed less as temperatures drop, stopping entirely in very cold water when fish cannot properly digest.

Seasonal Care in Wyoming and Cooler Climates

Because koi and pond fish are cold-water species, seasonal changes matter, especially in cooler climates like Wyoming. In spring, fish wake up hungry and water quality can swing as the biological filter catches back up, so test often and feed lightly at first. Summer brings peak activity and warmer water that holds less oxygen, making strong aeration important. In autumn, gradually reduce feeding as temperatures fall, and through winter focus on stability, keeping a small area of an outdoor pond open for gas exchange and avoiding disturbance of dormant fish.

Choosing the Right Pond Fish for You

The right pond fish depends on your space and goals. Classic koi and butterfly koi are the heart of any pond, while the Chinese Highfin Shark adds an unusual, sail-finned centerpiece for keepers with serious room. If you are newer to the hobby or working with a smaller setup, you may want to start with hardy options from our beginner fish selection or explore other oddball fish first, then graduate to a full pond as your experience and space grow. Whatever you choose, plan for the adult size of your fish from day one.

Frequently Asked Questions

How big do koi and Chinese Highfin Sharks get? Koi commonly reach 12 to 18 inches or more, and Chinese Highfin Sharks can exceed two feet, so both need a pond or a very large aquarium as adults.

Can pond fish live indoors? Young koi and highfin sharks can be kept in a large indoor tank, but adults do best in a pond or oversized system because of their size and waste output.

Do koi and pond fish need a heater? No. These are cold-water fish that prefer cool, well-oxygenated water, so outdoor ponds usually need no heating, while indoor tanks simply need stable, cool temperatures.