Weed Killers and Removal Techniques That Won’t Hurt Pond Fish

Weed Killers and Removal Techniques That Won’t Hurt Pond Fish

You have a beautiful pond in your backyard, and it’s filled with the most beautiful little pond dwellers and plants. Indeed, it would be completely picturesque if not for the horrible weeds that are encroaching all your gorgeous backyard. 

If this is what is happening in your life, it’s definitely time to go for the weed killer to fight against those encroaching plants.

However, before you go on your murder spree, you’d best make sure that you’re not going to be killing your fish and pond pets when working to take down those pesky weeds. 

Risks of Some Weed Killers

As you may have gleaned, there are risks associated with choosing just any weed killer off of the shelf. Most weed killers contain chemicals that are harmful to aquatic life, so it’s best to be aware of what you’re using before you start spraying!

Now, this may be one of those moments where you think that you want to go all-natural so that you can make sure you know exactly what you’re putting into your pond, but hold on before you start mixing. 

Most homemade weed killers use white vinegar, salt, and dish soap liquid. Now, while this might be fine for general spraying around your pond, you have to be careful about potential runoff that might end up in your pond.

These chemicals can have adverse effects on your aquatic friends, so, this is one of those odd moments where it’s safer to go with specific types of treatments for your pond rather than relying on home remedies.

What Kinds of Weeds Are You Dealing With And Some Treatments

Typically, when it comes to the types of weeds that you might be combating around your pond, there are four types: weeds around the edge of your pond/floating weeds, emergent weeds that are inside the water of the pond, submerged weeds in the water, and algae that don’t have roots.

Depending on the type of weed will determine how you handle it.

Just a quick note—note that the growth of aquatic weeds is natural and, actually, quite important to the ecosystem within your pond.

Weeds provide natural filtration, food, and habitats for fish and other aquatic creatures; the problem comes when they grow excessively.

Knowing this, don’t eradicate all the weeds! Just the ones that are growing too powerful for their own good—these weeds can block sunlight (which can negatively impact the nutrients your fish have access to) and even damage the build of your pond.

Weeds Around the Edge/Floating Weeds

The easiest way to remove these is to do so manually.

Reaching in with your hands (don’t have any toxic chemicals on them) or even with a rake or net are some of the best methods for combating these particular types of weeds, but there are some chemicals you can use if you want to risk it.

​​If you want to go the route of chemicals, try to gravitate towards a contact or systemic herbicide like Ultra PondWeed Defense; this herbicide in particular breaks down quickly in water, which means there will be less risk to your fish.

Emergent Weeds And Submerged In the Water 

Fluridone is typically best for use in weeds that exist in the water, of which emergent weeds are one of them.

Emergent weeds are those that exist in small areas of shallow water; they will be partially submerged and partially above water, allowing them to mix water and earth in your pond.

Submerged weeds are ones that are mostly underneath the water, but the edges of them might exist above the waterline.

Unfortunately, short of yanking and pulling these weeds out by hand on a consistent basis, there isn’t much in the way of removing these weeds from your pond.

Depending on the species of weed, you may have to resort to chemical killers, but this will have a negative impact on the ecosystem in your pond.

Algae With No Roots

The best type of weed killer for this type of weed (and, also, weeds that lack roots) is a chelated copper.

Water that has been treated with chelated copper is safe for humans and animals—it can be used for swimming, fishing, watering livestock, irrigating turf, or working with ornamental plants.

Other Options for Killing Weeds/Non-Chemical Weed Killers

If you’re still worried about introducing any sorts of chemicals to your pond and your fishy friends, you can also look into non-chemical methods.

UV Clarification

Free-swimming algae can be broken up and removed by using UV clarifiers. Having said that, this method is much better for smaller areas, and may not be suitable for bigger bodies of water such as lakes. 

Because this method just uses UV lights to break apart the algae, it is safe for fish, wildlife, and micro-organisms.

The strong UV light that is emitted from these units will destroy free-swimming pond algae at their cellular core, which causes them to break down and clump. From there, they can be sucked up by your pond filter or even be left to decompose. 

Manual Removal

This may not be too exciting to see on this list, but it is possible that you can reach into your pond and manually remove any sorts of weeds and algae that you’ve found in your water.

If you use this method, make sure that your hands are free of toxic chemicals or other things that might harm the fish and plant life in your pond.

This method is the cheapest, but definitely the most time-consuming, but it is still a viable method, so this article would be remiss without its inclusion.

Feed Your Friends

Depending on the type of weed, fish species can be used to control problematic weeds. Koi, goldfish, and grass carp are known to munch on water lilies, water hyacinth, and water lettuce, among others.

Using your fish can help keep plants under control, but aren’t a great method for extremely overgrown ponds.

Do Your Research!

Most products that claim they are safe for use around animals and aquatic creatures have been tested and registered by the EPA.

This means that, in so far as modern science and medicine can determine, herbicides that claim they are safe for use around living creatures have been rigorously tested to ensure their safety to people, animals, and the environment.

No matter which type of weed killer you end up using, make sure to closely follow the directions that come with it.

Some products/chemicals will even sometimes list a waiting period for fishing, swimming, livestock, and other sorts of situations. Make sure you listen to these warnings!

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