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Bloodworms in Pond Filter: Beneficial, Not Leeches

"Leeches" in a pond filter were actually bloodworms—larvae of non-biting midges. They live in bottom muck and are fish food. Their abundance suggests few or no fish in the pond. No control needed; clean the filter occasionally and let nature balance the ecosystem.

About Gardening: Troubleshooting a Newly Inherited Pond: Overflow, Black Water & Dead Filter; Why Are My Pond Fish Hiding? Solving Murky Water and Skittish Koi; Green, Smelly Small Pond: Why Filters Fail and How to Fix It; Muddy Pond After Storm: Coagulant and Diversion; New 1000-Gallon Koi Pond: Filter Maintenance, pH, Vacation Feeding, and Adding Turtles/Frogs; Cleaning Pond Filter Media: Mud vs. Pond Gold; Building a Pond Filter: Buy, Don't Build; DIY Biological Filter for Small Pea-Soup Pond; Pump and Filter Setup for a Raised Deck Filter and Waterfall; Choosing an External Filter for a Whiskey Barrel Pond: Bird-Proofing and Debris Control

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