Goldfish and koi are amazingly resilient. As the water temperature rises in the spring, their metabolism begins to increase and they become more active. It is at this time that fish are most prone to health problems.

Because your fish have been using less energy, they required less food. Since they have not been fed since the water temperature dropped to 55 degrees, it is now time to clean the pond and begin feeding the fish again. This procedure can be tricky, so it is important to pay careful attention to water temperature, pH, and ammonia levels.

If your pond is under 1,000 gallons, it is probably best to completely empty the pond, clean it, refill, and adjust the water chemistry. This process will accomplish several important things.

*Decaying organic material in your pond can cause problems
*High levels of metals and salts can be toxic to fish and plants
*Plants often need grooming and re-potting in the spring
*pH is important (Make sure you adjust your pH to the appropriate (7.4 to 7.6) level and dechlorinate your water before reintroducing your fish.

In larger ponds, periodic partial water changes and a meticulous maintenance schedule will accomplish the desired result.