Garden ponds can become cloudy for many reasons. Algae growth, mud running off the garden into the pond, dirt stirred up from the bottom, and decomposing leaves can all contribute to clouding the water. A number of different solutions may need to be implemented before the pond becomes sparkly clear, says Green Vista Water Gardens.Continue Reading
If the pond doesn't have a pump and filtration system, install one. If has one already, try moving the water inlet as far as possible from the water outlet so there are no completely stagnant areas in the pond. Check that the system is large enough for the size of the pond, and upgrade if necessary. Seed the filter weekly with beneficial bacteria.
Remove any dead vegetation that has fallen into the pond. Try putting a layer of stones on the bottom to prevent mud from being stirred up that can cloud the pond. Raise the lip of the pond slightly with stones or foam to prevent muddy water from flowing into the pond from the garden or other surrounding areas. Try changing the water in the pond, remembering to add dechlorinators if chlorinated tap water is being used as the water source.
If there are fish in the pond, thin them out. Too many fish can overwhelm the filtering system. Make sure the fish aren't being over-fed. Check that sufficient aquatic plants are growing in the pond and add some if necessary.