Don't Panic! Black Rocks in Your Pond Are a Sign of a Healthy Ecosystem

Biofilms are complex communities of microorganisms that attach to rocks, plants, and other submerged surfaces inside a pond and they can have several benefits:

1. Nitrogen cycle: Biofilms can help cycle nutrients in the pond ecosystem by breaking down organic matter and reducing problem nutrients such as nitrogen and phosphorus.

2. Water quality: Biofilms can help to improve water quality by removing pollutants such as heavy metals and organic compounds from the water column.

Scraping a biofilm with a knife.

3. Habitat creation: Biofilms provide a habitat for various microorganisms, including bacteria, algae, and protozoa. These microorganisms form the base of the food chain in the pond ecosystem, providing a food source for larger organisms such as fish, crustaceans and aquatic insects.

Overall, biofilms play an essential role in maintaining the health and balance of pond ecosystems by regulating the nitrogen cycle, improving water quality and providing food for smaller pond species.