How to prevent pond turnover

How to prevent pond turnover

As the summer months heat up and the cool fall weather is right around the corner, be aware of pond turnover. This can be a stressful time on the fish in your pond. Plenty of aeration and water circulation can prevent fish kills from happening.

Pond turnover can occur in the spring, summer and fall. A summer turnover can occur when a cool rain mixes with the warm water in the pond. This usually happens on small, shallow ponds or lakes. The sun warms the surface water while the cooler water is denser and sinks to the bottom, making two layers in the pond.

Dead plants and any organic matter will sink to the bottom and decompose, taking away much of the oxygen. When a heavy rain or storm occurs, it can cause the layers of water to mix, stirring it up, further depleting the oxygen levels and causing what we know as a fish kill.

The same thing can happen in the fall as cooler weather arrives overnight. These fish kills can be much worse as the cold water at the bottom has remained there all summer long. No sunlight can reach the bottom in deeper ponds. Many fish kills in our area happen on small, shallow ponds during the summer.

Remember it is important to keep the water in your pond aerated or circulating to prevent stratification or the separating of pond layers. Keeping your pond circulating will provide an adequate and balanced oxygen supply.