Yes, your beautiful koi are wearing a slime coat.

A fishes slime coat refers to it's protective covering that helps it maintain it's immunity to disease and infection. When you handle a fish, you will notice it has an oily, almost lotion-like feel. That is the slime coat.

Stress can wear away the fishes ability to create this coat, which increases it's odds of contracting disease. You might put a cup of salt to every hundred gallons of water (see 'Salt' before doing this!) to help with conditioning the coat, and do what you can, especially in the Spring, to make life as stress free as possible for your fish.

Hiding places help when there are no plants to shelter under. Be as reverent as you can when doing fall and spring clean-up, too. There are also products available that help specifically with the slime coat. See our vendors section.