Hand Feeding Koi
In addition to the peace and tranquility of Pond Keeping, spending time with your Koi can be equally rewarding. Koi are very sociable and love a crowd of friends. They are less apt to be shy when they are in a large group.
Your Koi will eat from your hand, provided you have the patience to earn their trust and friendship. Here are a few helpful hints:
Feed them in the same place every time.
Drop a small handful of pellets and stay there to observe.
The bravest or hungriest will start to eat and the rest will follow.
They must see you when they eat.
Don't walk away from the pond before they start to eat.
Withhold food for a day if they won't eat in front of you.
Gradually, the Koi will equate you with food. This usually takes about 3 to 5 days. Tease them closer with small sprinklings of food. Put your hands in the water while they eat. The Koi will learn that food comes from your hand. Start with just a few pellets.
The bravest Koi will soon be nudging your hand. It is only a matter of time and all of your fish will swimming, jumping and splashing toward you every time you walk by the pond.
courtesy of: see link http://www.lagunakoi.com/Feeding-Koi-Koi-Information-sc-23.html