
If you want fish for your backyard pond, you may be trying to decide whether to get Koi or goldfish, or maybe both. Both kinds of fish are common in backyard ponds, and each have their advantages and disadvantages.
If you have a smaller pond, under 500 gallons, then goldfish would be the best choice. Since goldfish are smaller than koi, they can live in a smaller space. Goldfish are also very hardy fish, and easy to care for. Because of this, goldfish would be a good option for you, if you’re a new pond owner. Goldfish are also less expensive than koi, and easier to replace.
Koi require a bit more knowledge and better control of the water quality than goldfish, and so are better suited to someone with more experience in keeping a pond. Koi should be kept in larger ponds, over 500 gallons. The more space the koi have the better.
If you plan on having plants in your pond as well as fish, then goldfish would be a better choice. Goldfish will play around under the floating leaves of plants, but not disturb them. Koi on the other hand, will dig in the soil of potted plants, making a mess, and possibly knocking the plants over. This isn’t necessarily a problem, since koi ponds are generally larger and deeper, and don’t need plants for water quality and shade, as smaller ponds do.
If you do want to keep potted plants in your koi pond, you can try wrapping netting over the tops of the pots to keep the fish out. Another method is to place pea gravel 1″ deep over the soil, and then larger river rocks over the pea gravel.