What causes a pond to appear murky, with low visibility, or clear, where you can see six feet? The amount of particles suspended in the water column determines such conditions. Those particles may be algae, plankton, soil, or other sediments flowing into the pond with runoff. Contrasting conditions may vary by pond even short distances apart. Minimum clarity is needed. Without sunlight in the water, the pond cannot produce plants and beneficial plankton. High turbidity levels also create higher water temperatures that may stress fish. Ask our biologist to evaluate your water quality.