Algae Treatment Community Lake: Silver Lake Ohio | LG Sonic

Introduction

Two consecutive seasons of safe swimming, achieved without chemicals and independently verified.

Algae treatment for a community lake became a priority for Silver Lake Estates, Ohio, after recurring toxic blooms led to swim advisories over multiple summers. Silver Lake is a private community lake serving over 460 lot owners who rely on it for swimming, boating, and fishing throughout the summer season. The Board of Trustees maintains the lake as a recreational resource, where clear water is part of the enjoyment of living in the neighborhood.

In 2023, microcystin (a liver toxin produced by cyanobacteria) exceeded Ohio EPA’s recreational limit in every month of peak season. Swim advisories limited lake enjoyment during prime swimming season.

In spring 2024, the Silver Lake Estates Board of Trustees deployed two LG Sonic MPC-Buoys: solar-powered, chemical-free systems that monitor water quality around the clock and apply targeted ultrasonic treatment before blooms take hold. The results: two consecutive summers of safe swimming, with improvement across every measured parameter, independently verified by EnviroScience Inc., which has monitored the lake continuously since 2016.

The Challenge  

Silver Lake faced compounding conditions that caused harmful algae to return each summer.

Toxic blooms exceeding Ohio EPA thresholds.  In 2023, cyanobacteria reached 168,000 cells per milliliter. Ohio EPA’s high-risk threshold is 100,000 cells/mL. The lake exceeded it by 68%.

Microcystin above the safe limit throughout 2023.  Ohio’s recreational safety limit for microcystin is 8 µg/L. In 2023, every monthly peak at the beach location exceeded that limit. The highest reading was 14.8 µg/L in May, nearly double the threshold. At those concentrations, skin contact causes irritation and rashes, while swallowing the water can cause nausea, vomiting, and diarrhea.

A declining multi-year trend.  EnviroScience’s long-term monitoring showed water quality declining from 2020 through 2023, with the most elevated algae and toxin readings occurring in 2023. In addition, surface phosphorus and nitrogen ran above Ohio water quality targets during this period, creating conditions in which cyanobacteria thrive.

Algae Treatment for a Community Lake: The Solution

In spring 2024, the Board of Trustees deployed two MPC-Buoys, positioned to cover Silver Lake’s full surface area. Each buoy is solar-powered, operates autonomously, and requires no chemicals.

How the algae treatment works.  Cyanobacteria maintain their position near the water surface using gas vesicles, tiny air-filled structures that keep cells buoyant where light is available for photosynthesis. The MPC-Buoy emits precisely tuned ultrasonic waves that disrupt these vesicles. Without buoyancy, the cells subsequently sink to deeper water where there is not enough light to grow.

Crucially, the cells remain intact as they descend. This is the critical difference from chemical treatment: copper sulfate and other algaecides rupture cell walls and release microcystin directly into the water, thereby requiring a swimming ban for days or weeks afterward. Ultrasound, by contrast, causes controlled sedimentation. The toxin stays locked inside the cells as they settle naturally into bottom sediments, so residents keep uninterrupted access to the lake throughout the season.