Koi keeping has become a very popular pastime among water garden enthusiasts especially to enjoy during pond season. They are a colorful addition to any outdoor space and can easily become the topic of conversation due to their quirky and often funny personalities. Their beauty also adds to a serene environment and completes the Zen vibe you may desire for your yard. Koi are an especially hardy breed of fish, making them capable of living in just about any climatic condition as long as appropriate care is taken to meet their most basic needs. However, for pond enthusiasts with koi, spring can mean unexpected challenges. Be prepared with a spring survival kit for koi and the knowledge of how to prevent spring kill.
In the beginning of spring, the dormant aquatic life starts to become active. This increase in activity includes fish as well as bacteria and other microorganisms. In the right conditions, bacteria can rapidly reproduce and create environments that are stressful to fish. If pond conditions are left unattended, eventual fish loss due to "spring kill" may occur.
Often people don’t know what the term “spring kill” means. This commonly refers to seasonal fish loss due to a series of issues related to water quality. It is mostly caused by dangerous, oxygen-poor conditions. A low-oxygen environment is not only stressful to fish but also allows certain harmful microorganisms to thrive like ammonia, nitrite, and other chemicals that lead to algae blooms.
Unexpectedly warm spring days can give bacteria an unfair advantage. It supplies the energy that microorganisms need to aggressively metabolize and reproduce. However, these short periods of warm days have a nominal effect in raising the overall water temperature fish rely on to boost their metabolism and immune system. In this debilitated state, fish are vulnerable to sickness and disease caused by bacteria.
Despite any advantage microorganisms may have, there are easy steps you can take to prevent spring fish loss. Installing a pond aerator is the easiest way to prevent fish kill. The added aeration prevents oxygen depletion and creates a healthy aquatic environment by adding oxygen to the pond, circulating the water, and reducing bacteria growth. Place the diffuser (bubbler) near the surface, so it won’t stir up any debris, harmful gasses, or aggressively churn the water. Other essential items for a spring survival kit should include a master pond test kit to measure ammonia, nitrite, and nitrate levels, a pond thermometer to accurately measure water temperature, and pond cleaner tablets that emit a blend of beneficial bacteria, enzymes, and natural barley, which will not harm your fish or plant life. These tabs are designed to break down fish waste, phosphates, nitrates and other water pollutants. Also recommended is Algaecide to reduce algae blooms and pond salt to encourage protective slime coat production. When pond water temperature is consistently above 45°F, reconnect pumps and start up filters with UV clarifier to ensure proper filtration and a successful new year of Koi keeping.