How to Clean a Pond: 3 Cures for Muddy Water & Muck Removal
Pond water needs to be clear for good production of fish. Clear ponds produce several times the amount of fish than turbid ponds. Lets face it, clear ponds are much more fun to swim in! Most ponds become muddy after heavy rain, runoff, when ponds turn over or from excess decayed vegetation. Normally, silt or decay should settle out within one week’s time. Water clarity is normally 1 foot or more during most of the year. Fish production will be decreased in water with less than 1 foot visibility.
If pond water does not clear within a week’s time, the problem may be due to a combination of factors.
Turbidity is normal caused by clay particles suspended in the water that repel each other (colloidal clay) and will not settle out. This problem can be treated by adding material to the pond that causes these particles to clump and settle out.
Fish (such as bullheads and carp), along with crayfish, will cause water to be muddy due to their burrowing and feeding on the pond bottom. Remove these species and introduce predatory fish like largemouth bass or channel catfish. Ponds with a good population of predatory fish will not have crayfish problems and turbidity will be reduced.
Excessive weed growth decays and can become suspended. Heavy rain and runoff flush nutrients into the pond that weeds will thrive on. This weed growth then dies causing an overabundance of decayed vegetation or “muck”. Wave movement or wind can cause this “muck” to rise causing turbidity throughout the pond. Reducing fertilizer applications near the pond, maintaining septic system, redirecting nutrient-rich runoff away from the pond will all reduce nutrient level. This reduction of nutrients in the pond will in turn reduce weed growth and decay.
3 good control options are:
Gypsum (hydrated calcium sulfate) (available from fertilizer dealers) can clear colloidal clay problems. Scatter gypsum evenly over pond surface at the rate of 525 lbs. per acre-foot of water.
Aluminum Sulfate (Clear-Pond) is a second option for clearing colloidal clay. An application of 50 lbs. per acre-foot will clear pond within one week. Alum is best applied by dissolving in water and spraying over water surface.
If the pond is acidic (low pH) or soft water, add about 20 lbs. of lime (calcium hydroxide) per acre-foot of water. This may also help the clay to settle.
Beneficial Bacteria (AquaClear) is an option for pond muck removal. One gallon will treat 1 acre-foot of water. Best applied by mixing with 9 gallons of water. Normally, 4 weekly treatments will clarify the water and reduce the suspended solids.
Please feel free to email me or post questions you may have and I will respond accordingly.