Muck and weeds are a concern for everyone who lives near a lake or owns a pond. Muck is a slimy, moist substance made up of decomposing organic matter. You undoubtedly feel uneasy walking on it or swimming in it. It becomes more of an issue when it harbors dangerous bugs like leeches. Microorganisms live and consume dissolved oxygen in the mud. These microbes can lower the oxygen content of the water, which causes fish to perish. Hydrogen sulfide, which strains or kills fish, also causes a nasty smell that a waterfront property owner may have to deal with. For those who live close to a lake or pond, weeds and mud can provide challenges.