6 Tips for Keeping Fish Alive in Your Backyard Pond

C.E. Larusso
Written by C.E. Larusso
Updated February 28, 2022
Man looking at fish pond
Photo: DigitalVision / Getty Images

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Take advantage of your big backyard and install a fish pond, which will offer soothing water sounds and give an elegant organic look to your space. With proper care, your aquatic friends can live decades; read on to learn how to care for the fish living in your pond and ensure that they thrive.

1. Determine the Needs of Your Specific Fish

What kind of fish are in your pond? Each type will have different needs, and learning what they are will be essential in keeping them alive. Here are a few popular kinds of fish for backyard ponds and what they need to thrive.

Goldfish

Goldfish are resilient and able to handle many kinds of weather. They need about 50 gallons of water per fish. They eat a variety of foods, such as pellets and flakes, but also nosh on organic critters like mosquito larvae as well as plants growing in the pond. 

During the warmer summer months, they will require more food to satiate their fast metabolisms. On the flip side, during winter, they only need a low-protein wheatgerm-based food to match their slowing metabolism. 

Koi

Stunning koi fish make an elegant addition to any pond. They grow large, so they will need a pond to match, but they’re able to withstand colder temperatures like goldfish. Watch out for an overgrowth of algae that will deprive your koi of oxygen. 

Koi fish eat a similar diet to goldfish; they’ll snack on koi fish food pellets, vegetables, krill, dead leaves, and other organic things. Both koi and goldfish become lethargic in the wintertime, and won’t need to eat much—you’ll see them at the bottom of the pond, just hanging out until things outside warm up.

Minnows

Tiny minnows can thrive even in small ponds. They are easy to care for and don’t mind cold weather. Keep some floating plants, such as lilies, on the surface to create a natural water cover. Fish food can be sprinkled onto the pond’s surface once a week; the minnows will also feast on algae and small insects. To prevent birds from decimating your pond’s population, tie reflective fabric on the plants that surround the water. 

2. Clean Your Pond Regularly

While some fish eat dead leaves and other organic debris, too much can release toxins that can kill your fish. Use a skimmer net to remove dead leaves and other debris. Additionally, you’ll want to take care of any sludge that has accumulated on the bottom of the pond. 

Believe it or not, there are pond vacuum cleaners that can suction up any decaying matter living on the pond’s bottom. Hire a local pond cleaning service to complete a full cleaning—which requires draining the water and moving your fish friends to a safe space during the process—once every fall.

3. Buy and Maintain the Right Equipment

Cat looking at fish pond
Photo: Miss Alva / Adobe Stock

An artificial pond needs equipment to keep it clean and fresh.

Water Agitator

The agitator keeps water moving and aerated, preventing algae build-up and keeping nasty odors out. You can select a water feature such as a fountain, bubbler, or waterfall. An ultraviolet light is another option that will help mitigate algae growth. 

Pump

You should purchase a water pump powerful enough to circulate all of the water in your pond once every hour. If you have a 2,000-gallon pond, you need a 2,000-GPH (gallons per hour) submersible pump. 

Pond pumps start at $35 for 200-GPH and run up to $700 for 7,000-GPH. Make sure to check your pump periodically to ensure it isn’t blocked by debris such as dead leaves.

Filter

Look for a biological filter with dual duty that both keeps water free of debris so your pump doesn’t clog and removes chemicals that could hurt your fish. A biological filter will also encourage healthy bacteria growth, which, in turn, encourages healthy fish.

Skimmer

This boxed, filtered unit houses the pump and provides filtration and debris removal. Prices range from $50 to $500, depending on size and quality. To prevent your fish’s food from being pulled into the skimmer (and causing the fish to follow it there), buy a feeder ring that floats on the surface and keeps the food there.

Liner

The liner prevents the water from seeping into the group. Look for a 45-millimeter rubber liner, which often includes a 20-year warranty. Prices start at $25 for a 5-foot-by-5-foot liner, and up to $4,500 for a 50-foot-by-100-foot liner.

De-Icer

This heating device will maintain a small, thawed area in the iced-over pond during wintertime, allowing toxic gasses to escape, and letting oxygen in. De-icers cost $30 to $120, depending on the wattage, which is determined by the size of your pond.

4. Watch for Leaks and Repair Them Right Away

If you notice your pond’s water level dropping quickly, or the area around the pond is wet and there is no obvious reason for it, you may have a leaking pond. Get the leak repaired quickly to prevent any harm to your fish.

5. Monitor the Water Chemistry

Over time, as plants and other things fall into the pond and break down, chemicals can be released into the water, throwing the ecosystem out of whack. 

Check the water’s chemical makeup periodically to ensure nothing is off; liquid test kits and test strips are both available, and will check for ammonia, nitrates, pH, and phosphates. This is an essential step to keeping your fish alive (and healthy).

6. Grow Water Plants

Introduce new plants at the start of summer, when the water is warm and will support plant growth. Look for greenery that will inject oxygen into the water and add to your pond’s landscape, such as water lilies, Victoria cruziana, aquatic irises, lotuses, cattails, and water ferns.

Every five to six weeks, add some fertilizer to the water to help your plants thrive, and make sure to cut back leaves so they don’t cover the entire pond surface area.

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