Muddy Water

Muddy Water

Muddy water limits fish production in ponds because the phytoplankton (single-cell plants) at the base of the food chain must have sunlight to grow. Silt and mud deposits also cover fish eggs and fill the pond, and most pond fish feed using their sight.

Controlling the erosion in a pond’s watershed is essential for permanent control of most muddy-water problems. If livestock are muddying your pond, fence off the pond and install drinking troughs below the pond. Some fish species, such as bullheads and common carp, can keep a pond muddy. In this case, renovate the pond and start over.

After you have identified and corrected the source of muddy water, test your pond water for alkalinity. Ponds with low alkalinity also tend to have low hardness and variable pH, which can cause clay particles to remain in suspension for long periods of time. If alkalinity is less than 50 ppm, adding agricultural limestone may help clear the pond. Spread 2 tons of crushed agricultural limestone per surface acre following the recommendations presented in the Water Quality section. The limestone dissolves and releases calcium and magnesium ions that settle the clay over several weeks. Once the pond is cleared, the small algae begin to grow, and muddy water conditions are unlikely to redevelop.

If alkalinity is above 50 ppm or if adding agricultural limestone does not clear the pond, one of the following methods may help remove the clay from the water:

  • 500 pounds of organic material per surface acre, such as old hay (approximately 10 square bales per acre broken up and broadcast evenly over the pond surface), cotton seed husks, compost, or other similar organic material. Be careful using organic material in the summer, since decomposition may deplete oxygen and cause fish to die.
  • Apply 40 to 90 pounds of alum (aluminum sulfate) per acre-foot of water. The dosage depends on the severity of the muddy water. Treat moderately turbid water (can see about 12 inches in the water) at 40 pounds per acre-foot, but severely turbid water (can see less than 6 inches into the water) may require up to 90 pounds per acre-foot. This translates to about 200 to 450 pounds of alum per surface acre of water for a pond with 5-foot average depth. Alum removes alkalinity from ponds, lowers pH, and can lead to fish kills in ponds with low alkalinity. To counteract this, apply hydrated lime at the same time as alum at half of the alum rate. Hydrated lime by itself can cause fish kills, so be careful when using this method to clear ponds.
  • Use gypsum (calcium sulfate dihydroxide) at the rate of 1,300 to 3,000 pounds per surface acre of water, depending on the severity of the turbidity. Spread the gypsum from a boat over the pond surface, and stir with an outboard motor. The gypsum keeps the water clear as long as the gypsum is not washed from the pond. When used according to recommendations, it does not kill fish, change the pH of the water, or harm livestock. When water clears, you can return to your regular fertilization program.
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Large, silver fish swim in blue water.
Filed Under: Fisheries, Fish Management, Marine Resources September 1, 2021

Fisheries experts at Mississippi State University and other research institutions are conducting an $11.7 million study of the greater amberjack, an important recreational and commercial species in the South Atlantic and Gulf of Mexico that is threatened by overfishing.

Woman in wading pants collects a water sample in a creek.
Filed Under: Healthy Soils and Water, Pond and Lake Water Quality, Pond and Lake Topics, Pond and Lake Management Resources August 19, 2021

STARKVILLE, Miss. -- Recreation in and around water is a great way to get outside in the warmer months and still stay cool. Whether you enjoy boating, fishing, swimming, kayaking, wildlife watching, exploring creeks and streams, or paddling coastal bays and estuaries, Mississippi’s waterways have a lot to offer.

Girl in a blue T-shirt and baseball cap holding a small fish.
Filed Under: Environment, Fish Management June 18, 2021

Grandpa cast the jig and cork to the center of the pond and handed it to Lucy. “Now, start reeling in slowly,” he said.

She did as Grandpa instructed. On the third crank of the reel, the float disappeared several inches below the water surface, and Grandpa shouted, “She’s got it; reel it in!”

That day, Lucy perfected her casting technique and caught nearly a dozen small bass and several large bluegill.

Graphic showing red snapper count in the Gulf of Mexico.
Filed Under: Fisheries, Fish Management April 14, 2021

BILOXI, Miss. -- The results of the Great Red Snapper Count are in!

In 2017, a team of fisheries experts began a two-year task of estimating the population size of red snapper in the U.S. Gulf of Mexico through this unprecedented, federally funded $12 million project. Scientists from several Southeastern universities and institutes, including Mississippi State University, used a variety of methods across the Gulf to accomplish this ambitious goal.

Bright green burweed in a patch of dead grass.
Filed Under: Lawn and Garden, Turfgrass and Lawn Management, Weed Control for Lawn and Garden, Weed Control January 14, 2021

Having “stickers” in your yard can be quite the nuisance. Stumbling upon a patch of stickers while walking barefoot is a painful experience. Plus it’s painful for your four-legged family members! Formally known as lawn burweed, these winter annuals are no fun to deal with.  

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Portrait of Dr. Wes Neal
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Fisheries Extension