Setting Up a Quarantine Tank
Setting up a tank about 200-500 gal. Use your pond water and build its own filter, fill with some of the existing filter media and cycle your water through the filter once an hour. Keep your new koi in this quarantine tank for at least 3 weeks. Keep its top covered with net to prevent jumping, and half cover with dark plastic for security so the fishes have less stress.
New Koi may carry bacteria or parasites, therefore treat them with medicine or chemicals. If Koi appear clean and healthy, treat only with rock salt (Using 5-lb/100 gal). If you need water change, always use existing pond water to give your new koi a chance to get use to your pond contents. After three weeks or more, when Koi appears strong and healthy, release the Koi into your pond.
When You Get Home
Place the unopened bag with y our koi inside the quarantine tank to float until the temperature becomes the same (about 30 min.). Then release koi and water into a clean tub and add pond water (same or more than the amount of water in the bag) let it set for a minute or two and release only Koi into the tank, dump the water. It will take about a day or more for your fish to settle down. Avoid laud noises and quick movements around your fish. Fish have a natural mucous coating for protection against parasites. Handle fish as little as possible.
The Need for Filtration
All fish give off wastes. In nature, bacteria that live on rocks and gravel in streams and lakes break down these wastes. We must simulate these conditions by passing water through a filter medium such as gravel or matting in a container outside the pond or aquarium.
Feeding Your Koi
For many people this is the best part. Be careful. Go easy until your water system and fish are established. Adult koi are vegetarians. Koi like chopped cabbage, lettuce, sliced citrus fruit and any similar food, including of course duckweed and other aquatic plants.
Koi will eat bread, cooked rice and cereals. The most balanced food consists of commercially prepared koi and goldfish pellets. But fresh vegetables are always good.
Do Not Overfeed
Remember that your filter must handle all the waste from your fish later on. The more you feed, the more waste material there is. Healthy Koi will always be hungry. Your must decide when they have had enough.
Outside, under ideal conditions, Koi will grow at a fantastic rte. The first year, fish will grow to be five to eight inches. If properly cared for they will grow an additional four to six inches each year until they have grown over two feet long.
Fish kept in small quarters will not grow as fast. Many fish seven to eight years old are not yet a foot in length. It is up to you, regarding the environment you wish to provide.
You will have healthier fish if you draw off about one inch of water from the bottom of the aquarium or pond and replace it with fresh water each day. When adding replacement water, follow the directions of a product to remove chlorine and chloramines. Your fish will thank you. Changing some water each day is a good practice even with a suitable filter.