Key takeaways for pond aeration

• Circulation and aeration oxidize and hasten phosphorus removal. They also support aerobic bacteria that utilize nutrients and decompose organic matter.
• Bubblers that circulate from the bottom are recommended over aesthetic fountains.
• Pond water temperature stratification affects nutrient cycling and oxygen in the water column. Shallow ponds may have warmer temperatures and support larger populations of algae and plants. Bottom aeration eliminates stratification and circulates oxygen through the water column, creating a preferred environment for beneficial bacteria and fish.
• Increased oxygen through bottom aeration transforms phosphorus into forms that algae cannot use.
• Fountains are inefficient and should be used for decorative purposes only.
• Stormwater ponds have high nutrient levels and require more management.

General takeaways:

• Algae varieties have different requirements for growth, but they all require nitrogen, phosphorus and sunlight to multiply and bloom. Reducing nutrients is a key management objective to reduce algae blooms.
• Vegetative buffers prevent nutrients from entering the pond.
• Blue-green algae (cyanobacteria) can produce toxins that are deadly to animals.
• Annual pond maintenance contracts range $200 – $2000 per acre (circa 2014).
• Dredging is required to remove nutrient rich sediment and weeds and increase the depth. Dredging is very costly, and dealing with removed sediment can be difficult.
• Grass carp can negatively affect the balance of the pond ecology and do not eat filamentous algae, cattail, fragrant water lily, or other large plants. They are not legal in many states.
• Barley straw has inconsistent results as a control agent.