But when plants interfere with fishing and access to the pond, they have become weeds. Corrective measures are either chemical, biological or mechanical. Chemical control involves applying an aquatic herbicide approved for this use by the Environmental Protection Agency. The third method of aquatic vegetation control is mechanical, or simply pulling the undesirable plants. This only works if there are not too many weeds to remove.
Water quality can be a problem in ponds.
Pond water can range from crystal clear to pea-soupy green, but neither extreme is desirable. Phytoplankton, the basis of the pond food chain, require sunlight and feed on nutrients in the pond water. These tiny plants are eaten by zooplankton, tiny animals that form the next step in the food chain. Zooplankton are food for insects and invertebrates, which are eaten by tiny fish. Progressively larger fish eat the smaller fish until humans complete the pond food chain when they catch a beauty for the dinner table.