10 Sure-Fire Methods to Protect your Koi from Predators & Pests (2020)

Protecting your koi pond and fish from predators is something every pond owner needs to be addressing.  It is the case that people have woken up to the horrific discovery that their fish have disappeared with no explanation. 
There are so many aerial and ground predators out there that the possibility of your pond turning into a midnight sushi bar is pretty good but luckily there are options out there to protect your fish.  From underwater koi houses to motion activated sprinkler units I think you find a solution here that works for you.

Pond netting

Simply stretch this netting over your pond to keep wading birds and raccoons from stealing your fish.  Pond netting is not very expensive and is a common tool for many pond owners.

Decorative metal grating

This is a real aesthetically-pleasing solution for both enhancing the look of your pond as well as protecting your fish from predators.  And because its strong metal there is no danger of kids or pets ending up in your pond.
decorative metal koi pond covers

Fishing Line

If you don’t want to quite commit to netting or decorative metal grating there is another solution that is more DIY and less costly. Its a trick where you string fishing line across your pond in a criss-cross pattern. This acts to trip up wading birds that may be stalking your fish.  An add-on to the fishing line trick is to add CD’s to the line so that they kind of hang there and spin with the breeze. This causes flashes of light and generally creates an environment that wading birds don’t want to be in.  Simply hang the CD’s from the existing line and you’re good to go. 


koi pond with deep drop off

Certain kinds of edging styles that give the edge a dramatic drop off will prohibit wading birds from being able to walk the perimeter of your pond and therefore they will be unable to nab your fish.

Pond dye

Predators can’t steal what they can’t see. Pond dye does just that, it hides your fish with harmless dye tinting.  The other benefit is that pond dye does a great job of limiting the amount of sunlight that penetrates your pond water and hence it reduces algae growth.

Mosquito dunks

Speaking of pond pests, mosquitoes seem to be an ever-present annoyance around ponds. Consider a tried-and-true solution, the mosquito dunk.  Its a small donut-like object that is impregnated with a virus/bacteria that attacks mosquito larvae so they never reach adult hood. Its harmless to your fish, frogs, turtles or pets.  Its easy to use and lasts a good long time.

Protecting your plants

Pests like raccoons are an obvious guilty party when it comes to koi ponds but what about your fish themselves? Your fish are curious and hungry and your pond plants may take the brunt of that by getting eaten.  Luckily there is a floating net protector that will keep your fish at bay and your plants safe. 

Surface cover plants

You should have a good deal of surface cover aquatic plants anyway but besides providing shade to your pond plants provide places to hide and generally not be seen by would-be predators.
aquatic-plants for koi ponds


There is a mechanism you can install near your pond that will actually sense predators like raccoons, wading birds etc. if they get near your pond and spray them with a pop up sprinkler head. Its kind of like the ol’ squirt bottle some people use on their cats when they get on the couch except this is always vigilant.  Night and day this thing is ready to give pests and predators what for (and you can even set it to double as a regular lawn watering sprinkler too).


Blue herons are a common wading bird that has its eyes on your fish. They are also territorial so one solution that a lot of ponders use is a blue heron decoy.  Just set this guy at the edge of your pond and would-be visiting herons move on after seeing that your pond is already occupied.


Kind of like bomb shelters the “Koi Kastle” shelter by Nycon will physically protect your fish and give them a safe place to hide.  Its a hard plastic tunnel that sits on the bottom. Easy to install and effective. 
If your pond had all of these predator and pest “counter measures” you would certainly be the envy of all the other pond owners in your region (and would probably make the cover of “Koi Pond Defense Magazine”…if it existed). However, its likely you won’t need all of these mechanisms to defend your fish from disappearing.  Just a few will most likely be sufficient.  Its helpful to know what your options are though so I hope you found this list inspiring. 

2 thoughts on “10 Sure-Fire Methods to Protect your Koi from Predators & Pests (2020)”

  1. You said that these suggestions are for “when it gets warmer” but I’ve lost a lot of fishes over the past 3 months while it’s been cold. I didn’t cover my pond with netting this season and have regretted that because something(s) have turned my pond into a midnight sushi bar. I did see 1 raccoon but he mysteriously died (probably poisoned by a neighbor) and I thought the culprit had reaped his just reward. However, I continue to lose fish. So what can be the culprit that roams in these unusually cold winter months in NC?

    • Hi, in NC you certainly have aerial predators like wading birds (great blue herons etc.). Otters may come and go as well. Sorry to hear you’ve lost fish-its definitely frustrating.

      2.5 is pretty deep for a wading bird, they’re snagging fish in a foot or less. Raccoons are most likely not getting fully submerged for a fish. Osprey are certainly capable of snagging a fish off the surface at any depth and of course otters. Once a predator figures out a good spot to hit with minimal effort and competition they will keep going back.


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