Introduction
Many water gardeners prefer to keep goldfish in their ponds, rather than koi. While koi are beautiful, they require a large pond and often carry a large price tag. For the water gardener who does not have the room for or the desire to invest in koi, goldfish are the answer. Their vibrant colors, small size, reasonable price, and ease of care make goldfish a popular alternative for the pondkeeper.
Myths About Goldfish
We've all seen the famous "goldfish toss" at fairs, fund-raisers, and other carnival-like events. Simply toss a coin or ping-pong ball into the fish bowl and you've got yourself a fish. For some reason, people think goldfish are "bullet-proof," but this is not the case. While goldfish can tolerate a wide pH and temperature range, they are no less delicate than tropical fish. Perhaps the image of 1000 "feeder" goldfish packed into the 30-gallon aquarium leads to this conclusion. The fact is, goldfish require good water quality and proper feeding, like any other fish. In addition, some goldfish can survive cold-water conditions, while others must be brought indoors if the temperature drops below 60°F. Goldfish are not garbage disposals, eating anything tossed into the water. The days of feeding goldfish bread scraps, dog food, and breakfast cereal are over. Goldfish require a balanced diet, just like any other fish.
Speaking of Food.Goldfish are omnivores. They eat plant and animal matter such as algae, plant fragments, and insects. Some people never feed their goldfish. They rely on bugs falling into the pond and the fish's ability to graze on algae. For most pond keepers this is just too boring. We love to watch our fish come to the water surface and eat. Feed your fish either pellets or flakes. PondCare Spring and Autumn Pond Food and Summer Staple Pond Food are excellent pelleted diets for goldfish. Your fish may be used to flake food. Goldfish kept in ponds eagerly eat Aquarian Goldfish Flakes. Either food will provide your fish with a complete diet formulated especially for pond fish.
Goldfish may be fed several times a day. It is important, however, not to add too much food at one time. Goldfish are grazers, feeding continually as they swim around in the pond. The idea is to provide them with several small meals during the day. This makes for easy digestion and nutrient absorption. Most pondkeepers feed their fish once in the morning and again in the afternoon or evening.
Warm Water Goldfish Varieties for Water Gardens
The following is a list of goldfish suited for warm water ponds. These fish will thrive in a water garden as long as the temperature stays above 60°F. The fish must be brought indoors if the temperature falls below this critical level. Black moors are the most common type of fancy goldfish. They have an egg-shaped body with telescopic eyes. Although black moors are quite hardy, their bulging eyes are prone to injury, which leads to bacterial and fungal infection. The black moor has a beautiful veiltail, that is attractive when viewed from above. The lionhead is an exotic goldfish for a number of reasons. Through selective breeding, the fish has lost its dorsal fin and gained a bumpy "lion's mane" on its head. In Japan, this fish is called the ranchu. The bumpy growth on its head is called a wen, or hood. The lionhead cannot compete with more aggressive feeders. The lack of a dorsal fin and a short body makes it difficult for the lionhead to swim quickly. Lionhead goldfish may require hand-feeding if they cannot eat with other fish in the pond. The oranda has an unusual tissue growth that looks like a cauliflower cap on its head. These graceful fish are available in a variety of colors including redcap, white cap, chocolate, and calico.
Bubble-eye goldfish have large fluid-filled sacs under each eye. Like the lionhead, the bubble-eye lacks a dorsal fin. For these reasons, bubble-eye goldfish must never be kept with aggressive fish. Rough surfaces, sharp objects, and strong water currents are dangerous to bubble-eyes.
Cold Water Goldfish Varieties for Water Gardens
The following goldfish are winter-hardy. These fish can remain in the pond throughout the winter, provided the pond is deep enough to protect them from freezing. Shubunkins, also known as calico goldfish, are a very popular variety of goldfish. Shubunkins have a mottled pattern of white, red, black, and blue, with long graceful fins. They are an active fish that add a flash of color to any water garden. Sarasa comets have a deep red and white color pattern and long fins. These active fish are easy to take care of and grow up to ten inches. Fantail goldfish have an egg-shaped body and a "split" or double tail. Their unusual shape and tail prevents them from being strong swimmers. Fantails will not thrive where they have to battle fast currents and compete for food 
with more aggressive feeders. Fantail goldfish are available in many colors including red, red & white, and calico.
The Ryukin goldfish looks similar to the fantail, but has more of a humped back. Like fantails, Ryukins prefer quiet waters with fish of their own kind. There are many color varieties, including chocolate, bronze, red, and calico.
Final thoughts
When selecting goldfish for your water garden, be sure to select healthy fish. While "feeder" goldfish may look like a good deal, they could introduce disease into your pond. Purchase fish that are in clean aquariums or ponds and appear to be lively and colorful. Many water gardeners quarantine their new fish in an aquarium or holding pond for a week, before releasing them into the pond. Most disease problems will surface within a few days of the quarantine period. It is easier to treat one sick fish than an entire pond of goldfish. Lastly, don't be surprised if your new fish do not eat right away. It may take a few days for the fish to adjust to their new surroundings.