If you have a decorative pond in your yard, chances are that when you built your aquatic oasis, you selected koi and goldfish from a tropical fish store to populate it. Although these fish are beautiful and thrive well in a pond environment, they can cause problems with the environment if they every reach another body of water. This may sound far-fetched, especially since these fish can't walk. However, a large rainstorm that causes your pond to spill over, or a water fowl that transports the fish in an attempt to feed, can relocate them from your pond.
Koi and goldfish breed quickly, so they may rapidly outnumber indigenous species of fish. In addition, koi and goldfish are able to tolerate low oxygen levels. This is beneficial for ponds that are sometimes not optimally aerated. However, in the wild, it gives these fish another advantage over local species that may not be as tolerant to changes in oxygenation. These fish are also herbivores with large appetites, so they eat great amounts of pond vegetation and root in the soil to further compromise the oxygen levels that may be essential to neighboring fish. Still, koi and goldfish are not the only options that tropical fish stores offer to populate a pond. Here are two others:
White Cloud Mountain Minnows
White Cloud Mountain Minnows originated from China. The species is quite small and may not exceed 40 millimeters in length. Although they are fun to watch as they swim about in groups, they do not have a large detrimental impact on the environment. In addition, due to their size, they are suitable for small and large ponds.
These fish feed on small insects, worms and zooplankton. Additionally, they enjoy some degree of shade, so be sure to include floating vegetation in your pond.
Paradise fish occur naturally in China and Vietnam. These fish are relatively mid-sized among aquarium fish; they can grow up to 80 millimeters in length. Since they like to feed on insect larvae, they may benefit your outdoor space by keeping your mosquito population low. In addition, they have the ability to receive oxygen directly from the air, so they do not have to live in a generously aerated pond environment.
If you have a pond or are planning to install one, you may be considering various species of fish to inhabit it. Visit a tropical fish store, like Neptune's Tropical Fish, to learn which fish are most suitable for your project.