The Problem with Copper Sulfate for Treating Surface Water

From country club ponds and private lakes to protected wetlands and public waterways, harmful algae blooms (HAB) pose a major problem wherever they develop. Cyanobacteria release toxins that poison wildlife, kill off microbes, and put undue duress on the ecosystem for as long as it’s allowed to persist. Those charged with remediating (and preventing) HABs find themselves faced with an important question: how?

There are plenty of products designed to destroy HAB-forming bacteria, including copper sulfate, which has proven itself as one of the most popular and accessible solutions. But at what cost? What many water management personnel don’t often consider when using this product is, dumping copper sulfate into HAB-infested waters does more than destroy harmful bacteria — it throws the entire microbiome into disarray.

Understanding the problem with copper sulfate

Copper sulfate is an algaecide, bactericide, and fungicide that works by binding copper ions to functional groups of protein molecules in fungi and algae, which causes protein denaturation that produces cell damage and leakage. These toxicological implications are indiscriminate. Copper sulfate can’t “target” unwanted organics, which means the entire ecosystem is affected wherever it’s deployed.

Put another way, copper sulfate throws an already out-of-balance ecosystem further off its axis. HABs thrive when the microbial community is out of balance. Copper sulfate takes an invasive approach to eliminating an invasive species, often at the expense of good bacteria. For instance, it will eradicate zooplankton such as daphnia and rotifers, which are crucial for the stability of the local microbiome.

On a larger scale, plant and animal life can suffer from overexposure to copper sulfate. There is no reference dose (RfD) established for copper sulfate, leaving water treatment professionals prone to overtreatment. Numerous studies on the effects of copper toxicity in fish and wildlife show detrimental effects from overexposure, ranging from acute illness to death.

Recognizing copper sulfate’s inadequacy as a solution

The reason copper sulfate continues to be the HAB treatment of choice for lake associations and other water treatment demands is simple: Seeing is believing. After dumping copper sulfate into a body of water and seeing HABs disappear, many are apt to believe in the treatment. Unfortunately, it’s impossible to see the microbiological devastation that accompanies these “results.” Accordingly, copper sulfate treatment appears fine on the surface.

But consider a longer-term impact — HAB might disappear overnight after a copper sulfate treatment, only to begin forming again a few weeks later. Plus, it’s likely that the same blooms will resurface next year, often with more intensity than in the past. The reason? As copper sulfate treatments compound the damage to the biological ecosystem, aggressive cyanobacteria will more readily outcompete good bacteria in the future.

Every copper sulfate treatment is an incremental contribution to the problem, disguised as a solution.

Striving for a harmonious microbiological ecosystem

Copper sulfate as a means of alleviating HABs is a classic example of treating symptoms, not the problem. Worse still, it’s an active example of enabling the problem. It treats the visible symptoms of cyanobacteria while destroying the moderating bacteria that bring balance to the microbiome. So what’s the solution?

The answer to long-term, sustainable relief from HABs and cyanobacteria is to introduce enough good bacteria into the ecosystem to outcompete the bad. In the case of the EBS-Di, bacillus bacteria offer a natural solution. Not only will bacillus bacteria completely remediate HABs — including the elimination of toxins like microcystin — it can also restore bodies of water to a natural, healthy state that persists long-term.

Bacillus bacteria are already part of the natural ecosystem (found in soil). When introduced en masse into HAB-infested waters, these bacteria create and sustain balance against the constant influx of organic materials and phosphates. It’s a solution that remediates, prevents, and sustains — all by bringing balance to the microbiome.

Treating the problem, not the symptoms

While it’s simple enough to dump copper sulfate into the water and watch HABs shrink to nothing, unseen damage to the local microbiome isn’t worth the price. The better solution is to attack HAB problems at the source: the cyanobacteria that form them. Outcompeting these bacteria means not only preventing HABs and the problems that accompany them, but also restoring balance and longevity to the local microbiological ecosystem.

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