Parasites Harmful To Pet Fish and How To Prevent Them

Parasites Harmful To Pet Fish and How To Prevent Them

It’s an unfortunate reality that fish get sick. As an owner, you should do everything you can to educate yourself on diseases and parasites that can cause your fish to become ill. This knowledge will hopefully allow you to handle the situation better. Doing this will also allow you to have a better understanding of the diseases and parasites that are harmful to your pet fish and how exactly you can prevent them.

If your pet does become ill with a parasite, it is important that you separate the fish from others in the aquarium. Below are a few different parasites that could harm your pet and how you can prevent them.

Anchor Worms

This parasite harms fish by using its anchor-shaped head and burrowing it into the fish’s flesh. You can often tell that an anchor worm has attached itself because the fish will bleed at the attachment site. Be careful when pulling this parasite out, as it may cause the fish to bleed even more.

Fish Lice

Fish lice hide themselves by camouflaging to the color of the fish. This can make detection difficult. However, if you see your fish scratching or rubbing its body against anything in the tank, they may be trying to get the lice off them.


There are two different types of flukes that can harm fish. The first type is the skin fluke, which attaches to the skin of the fish and causes the fish to swell. The second is the gill fluke, which attaches to a fish’s gills, making it hard for the fish to breathe. You can spot gill flukes if you notice that your fish’s gills have turned pink or if the fish stay toward the water’s surface in hopes of breathing better.


This parasite feeds off the blood of the fish. They can be harmful or even deadly for the fish, depending on how much blood they take. Be careful when detaching the leech from your fish, as there is a good chance that the leech’s jaw will stay attached to the wound. Use your fingernail to break the leech’s seal and detach its jaw.


This parasite is also known as ‘ich’ or ‘white spot’ and is the most common parasite among pet fish. When a fish encounters this parasite, it loses its appetite, hides frequently, and rubs itself against objects in the tank. This disease can spread quickly, so be sure to quarantine the infected fish as soon as you notice a problem.

Pay attention to your tank and your pet. If you pay close attention, you should be able to notice all these diseases rather quickly. Keep your tank clean to further prevent parasites and diseases. You can use certain antibiotics, such as Praziquantel, to help fight against parasites as well.