A fish pond can be an attractive and rewarding addition to your land that helps to attract wildlife, stores water in times of drought, and provides a swimming hole for your kids — all while producing fish for your table.
Raising your own fish give you the peace and serenity of private access to your own fishing hole, and it also can provide a unique opportunity to encourage a fishing hobby in your children, since they’re much more likely to make a catch in a stocked private pond.
Whether you have a pond on your land already, or are considering constructing one, it’s important to consider that a pond will require maintenance to stay attractive, healthy and productive. To take proper care of a fish pond, you’ll need to maintain a depth, prevent chemical contamination, and minimize algae growth.
Pond Size and Depth
While it may be tempting to hand dig and stock a miniature pond in your backyard, ponds under half an acre of surface area have trouble supporting stocked fish in the long term. Below half an acre, the pond just doesn’t have enough space to keep a thriving population alive, and it is likely to dry out in the summer or freeze solid to the bottom in the winter.
Deep water ponds are the only type capable of reliably maintaining a stable ecosystem for your fish year-round. Ponds with 25 to 50 percent of their area at least 10 feet deep are considered “deep-water ponds.” Depending on your climate, your pond may need to be significantly deeper than 10 feet to prevent winter kill of fish, or to prevent summer overheating for cold water species such as trout. Different fish species have different temperature requirements.
Minimizing Sediment & Evaporation
To maintain depth in a stream-fed pond, include a small sediment settling pond to slow the water and allow fine sediment to drop out before the water enters the main pond. Water should flow slowly out of the sediment pond into the main pond, and if designed correctly, should enter the main pond clear.
Ponds not fed by a stream have less concerns about sediment, but are more likely to lose depth in times of drought. Minimize surface area where evaporation occurs by having a round or oval pond shape with relatively steeply sloping sides. An irregular pond edge means more surface area, but also more shallow edge space that encourages evaporation without providing deep habitat for fish.
Preventing Chemical Contamination
It’s important to prevent chemical contamination of your pond, because what goes into your fish pond will eventually land on your family’s table. Ideally, avoid synthetic pesticides and fertilizers on your land, but if that’s not an option, do not use them within 100 feet of the pond or the stream that feeds the pond. Avoid mowing or excessively trimming vegetation within 100 feet of the pond, as well. This vegetation buffer zone helps to filter out contaminants and keeps your pond cleaner in the long run.
Preventing Algae Overgrowth
Excess algae growth in a pond can lower oxygen levels and suffocate fish, and certain types of algae can be toxic to both humans and fish. Algae blooms are caused by a number of complicated ecological factors, but the best way to prevent them is to limit or eliminate excess nutrients entering the pond. Abundant vegetation near the pond edge helps to absorb nutrients that would enter in run-off. Preventing runoff from agricultural areas, and keeping pets and livestock as far from the pond as possible, prevents their wastes from entering the pond to feed the algae.
Another way to prevent algae in a home pond is to add a small amount of hardwood ash to the pond. Hardwood ash promotes native vegetation by adding soluble minerals to the pond. When these minerals are lacking, algae can out-compete vegetation for the nutrients in fertilizer runoff. The minerals in hardwood ash help give vegetation a leg up over the algae and can prevent harmful algae blooms. It doesn’t take a lot to have a big impact, and it’s suggested that ash be added slowly, as too much can do more harm than good. The suggested rate of application is only 1 tablespoon per 1,000 gallons of water.
Choosing Fish Species
The type of fish will depend on your family’s tastes, your location and your pond’s specific ecosystem. Trout are a cold-water fish, and require deeper water (12 feet minimum) to stay cool in the summer months.
Other fish species, such as bass, thrive in warmer water, but require the addition of a prey species for food. With a predator and prey species in a pond, it’s important to maintain the right ratio of predator to prey to ensure the survival of the larger predator fish you intend to harvest.
To choose your fish species and stocking density, it’s important to talk to your local extension or to consult a fishery biologist, as pond ecology varies by region.
What advice would you add on maintaining a pond long-term? Share your tips in the section below: