Algae Corner: Why Algaecides Aren't Scary

Welcome to this critically important episode on why algaecides aren't scary. What we want to talk about today is specific US EPA-approved algaecides and how they can be efficient, effective, and ecologically-friendly tools in the fight against nuisance algae and toxic algae.

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Algaecides are specifically registered by the US EPA under a federal law called FIFRA. Under this law, any substance that's designed to prevent, destroy, repel, or mitigate algae needs to be registered as a pesticide or an algaecide. So just to be absolutely clear, if you're going to use a product to control algae, it must be registered for that purpose by the US EPA under FIFRA and the sites you plan on using it in must also be present on that approved label.

Overall, this registration is important to understand and is a very good thing. See, numerous independent studies go into getting this pesticide registration. They have to be submitted to and reviewed by the EPA, and then the EPA uses them to build the label instructions and directions. Studies include anything from “How does the product dissipate?” to “Does it bioaccumulate through the food chain?” to “Does it negatively impact fish wildlife associated with the water body?”. There are also a lot of studies related to human health such as “Does that product impact any human uses of the water or humans directly following its use?”.


The EPA Sets Labeling Requirements

Registered Algaecides Are Well-Researched

Again, the EPA summarizes all this data, literally hundreds of different studies, and then sets the label guidelines and instructions to pose negligible risk to humans in the environment following the algaecides use. Most of these algaecides are very widely used and can be used in a wide variety of water resources.

SePRO Algaecides Have No Water-Use Restrictions

At SePRO, all of our algaecides have no water-use restrictions following application. This means there are no issues with wildlife, irrigation, humans recreating or swimming, or use in potable water systems. Overall, there is very negligible risk to humans in the environment when the label is specifically followed.


EPA Registration Is Critical for Being Environmental Stewards

Negligible Risk to Environment

This process is critical to being environmental stewards and using approved products for control of any nuisance or noxious algae you may be fighting. Products without EPA registration should be faced with higher skepticism as they likely they don't have near as many studies, or even any studies, on their safety.

They don't have studies that deal with the non-target species. They don't have the quality control that the EPA mandates to keep a very tight look at the active ingredients. They don't have the studies that show whether or not they build up in humans or cause any human health concerns or risk to your dogs or bumblebees.

Overall, much more concern should be given to products that don’t have approved EPA labels and those studies behind them.


SePRO: Driven to Discover

SePRO Research And Technology Campus

Additionally, if you're basing your perception on algaecides and herbicides from some historic products, those might not be able to be used anymore and certainly may not be advanced like we are today. At SePRO, we've continued to make advancements in algaecides. Over the past decade we've come out with many different new and advanced products and chemistries.


Advanced SePRO Products


SeClear, for example, is the only two-in-one product, algaecide and water quality enhancer. We control the algae and keep it from growing back so we actually use less product through time. We don't need to go back as often because the algae doesn't regrow as quickly. We can be really selective and only take out the bad types of algae, leaving the good types.


 Captain XTR

Another product SePRO’s developed recently is Captain XTR. It’s very efficient, has a good affinity, and does a great job getting control of those nuisance and toxic types of algae. It can be twice as potent as many other products out there. So again, we're being more efficient with what we're using and overall using less through time to get the job done with the same control. We need to put less product out there in the environment.


PAK 27

PAK 27 is yet another product example. This breaks down into oxygen and water. It's NSF-certified for drinking water and OMRI-certified for organic use. It’s very safe for non-target species and the people associated with the water body.

These advanced algaecide formulations we’re involved with have only just recently have become very popular due to their efficiency. They’re much better than some of the older, out-of-date, historic chemistries that have a much worse toxicity profile and often pose more risks to the aquatic systems and human health.



Human Health Concerns

In summary, today we covered registered algaecides and why they're a useful tool in the fight against toxic, noxious, and nuisance algae. Registered algaecides have many studies behind them and a lot of quality control goes into getting them approved for use.

It's very important to read and follow all algaecide label directions because they are mandated by the EPA for the specific usages to control that pest. For each product, it’s very important to understand which algae it controls, at what concentration, and its use sites. At SePRO, none of our products have any restrictions on water-use after application.

SePRO Algaecides Don't Have Any Water-Use Restrictions

Overall, algaecides can be a highly-studied and very well-used tool. Regulatory approval of these products control nuisance algae at their use sites. So in general, if you think algaecides are scary, you might want to take a closer look and think again. With that approved label by the EPA, you can actually use them quite efficiently and effectively and minimize any potential risk to the aquatic system.

Thank you for tuning in to this critically important episode on why algaecides aren't really that scary and how they can be used efficiently and safely in your water resource to keep that water in good condition and good quality. As always, there is a lot more to learn in the Algae Corner series and on the rest of our site at