Deciduous trees drop their leaves every year and when these leaves settle to the bottom of your pond a slow release of nutrients occur as they are slowly digested by fungi and microbial bacteria. A healthy young pond or a relatively new pond will have a layer of aerobic bacteria present on the bottom that will facilitate the digestion of dead plant material and leaves. As a pond matures or accumulates yearly leaf deposits the layer of aerobic bacteria is covered and replaced by anaerobic conditions. Think of a sheet of plywood and how it is made by adding layers to form a dimensional thickness. Leaves will form stratified layers that keep getting thicker year after year unless they are stirred up or digested with the addition of probiotic bacteria.
Some thoughts to share:
- Dragging a chain across the bottom will de-stratify the leaves and help fungi or bacteria work faster but may cloud the water column
- If you have an aeration system, move the diffuser platform to different locations to mix oxygen into the accumulation of leaves
- Select the right type of probiotic bacteria to supplement the microbial digestion of organic sediments and monitor the effectiveness to adjust application rates if necessary
- Drain the pond and excavate the leaves and organic black muck
Maintaining a healthy pond is similar to taking care of your landscape or garden before it becomes liability
