Koi Ponds and Other Fish Ponds
What Kind of Fish Ponds Make Sense for Me?
There are all kinds of different types of fish ponds available. Some come ready made, just plug in and go - others need major constructions work. Some are suitable for large fish, others will only handle small ones. Sorting it all out is quite a puzzle, but this page can help.
The classic in-ground backyard pond is what most people think of when they think of a fish pond. In reality, there are lots of other ways that fish can be kept outdoors. For that matter, there are also indoor fish ponds.
The size and depth of pond you need to keep fish varies depending on the type of fish you want to keep, and on the climate.
All photos used under Morguefile license
Koi ponds
and Predator Prevention
There are several requirements for a good koi pond. The pond needs to be at least 1000 gallons in volume and three feet in depth. The volume is needed because koi grow over three feet in length, and the depth is needed both because of the size of the fish and to give protection from freezing and predation. It should be well-filtered and well-aerated. Part, but not all of the surface should be covered with floating plants to give shade and make fish less visible to predators.
Predator prevention
Whatever type of pond you have, this is important to ensure that your fish pond continues to contain fish.
- Create a deep area in the pond - more than two feet
- Submerged and floating plants provide hiding places
- Install a heron decoy - remove during the breeding season or it can attract rather than repel herons
- Use a floating decoy fish - when a predator attacks it, the real fish can flee
- Buy dull-colored fish - there's a reason most wild fish don't have bright orange backs
- Use milk crates as support for marginal plants - they double as hiding spots for small fish
Koi Ponds and Fish Ponds reference
Indoor and Indoor/Outdoor Ponds
Indoor Ponds
Indoor fish ponds are usually small, and are often container water gardens. In some ways, these are more like giant goldfish bowls in opaque containers than outdoor ponds. As they are indoors, they are cut off from natural wind and you won't have problems with freezing temperatures or falling leaves ending up in the pond. They can be filtered or aerated easily, and if you heat them you can keep true tropical fishes like guppies, swordtails or tetras. If you don't heat them, they can be home to white cloud mountain minnows, or rosy red minnows as well as the more traditional goldfish. Indoor ponds make ideal homes for fancy goldfish. Many fancy goldfish varieties were originally bred to be viewed from the top in containers like these.
Indoor-Outdoor ponds
These are usually ponds in containers that are moved inside for the winter and outside for the summer. They are good for climates where small ponds freeze solid in the winter.
What are your favorite kind of fish ponds?
Container ponds
A small pond housed in a container. These can't house koi, and depending on the size of the container may be able to house goldfish or only be able to house tiny fishes such as white cloud mountain minnows or mosquitofish. One thing to be aware of is such small, above-ground bodies of water heat and cool more rapidly than an in-ground pond.
High temperatures reduce the oxygen content of the water. This makes aeration and surface shading by floating plants more important than in a full-sized pond. A small, unaerated container of water in full sunlight is an invitation to dead fish.
They are also vulnerable to predators, since there isn't anywhere for fish in a small container to hide or flee to.