No one wants to find tiny worms wriggling around in their betta fish tank. Yuk!
If you spot a mass of tiny, stringy white worms living in the substrate, those are most likely detritus worms. These creatures feed on uneaten food, fish waste, and general detritus in your tank, hence the worms’ name. These worms are usually a sign of a dirty tank!
However, in this article, we’re taking a look at another common species of the wormlike creature called planaria that you sometimes find in your betta tank.
What are planaria worms?
Planaria belong to the ancient Platyhelminth phylum group of flatworms and are related to other similar creatures, such as liver flukes. Planaria can be found in saltwater and freshwater fish tanks right around the world, finding their way into your aquarium hidden in plants, rocks, substrate, and even attached to fish.
These fast-breeding worms are hermaphrodites, which means that they don’t need males and females to reproduce. Did you know that if you chop up a planarian worm into half a dozen pieces, you’ll have half a dozen fully-formed flatworms within a few days?
Most species of planaria graze on waste products in the substrate, although some are parasitic or predatory. These worms are deceptively advanced, having the ability to detect water currents through sensory apparatus in their heads and eyes, too. Planaria generally shy away from the light, preferring darker conditions and coming out mostly at night, which can make them difficult to spot.
How to identify planaria worms
Before you can begin treating the worms in your aquarium, you need to positively identify the species.
Planaria are around 10 millimeters long with flat bodies. The creatures have a triangular head with two tiny eyes that are visible, and the worms can be white, brown, grey, or even pinkish in color, depending on what food they have been eating. You will most likely spot these wrigglers sliding across your aquarium glass rather than living in the substrate, although sometimes you might spot a worm attached to your poor betta or one of his tankmates.
Are planaria worms dangerous to your fish?
Planaria worms do not generally harm healthy fish. However, they do love to feed on fish eggs, which is clearly a big problem for you if you keep egglaying fish along with your betta.
Some species of predatory, carnivorous planaria also attack the eyes and gills of weakened adult fish.
These creatures come in two broad types; those that eat detritus and those that are predatory.
Dugesia planaria worms
Dugesia planaria worms are black and brown. These creatures are harmless to fish. However, they feed on detritus, including feces, biofilm, and uneaten food. If you have a population of these planaria in your tank, that’s an indication of poor aquarium husbandry. If you have a very dirty tank, you could potentially finish up with hundreds or even thousands of these worms.
Although Dugesia planaria worms aren’t carnivorous, they can slide into the gills and other sensitive areas of fish, causing stress that weakens the fishes’ immune system and leaving the victims vulnerable to disease. However, if you have shrimp in your setup, these worms can be a big problem.
This species of planarians are thought to secrete a toxin that can poisons invertebrates. So, if one of these worms slithers inside a shrimp carapace, toxins could be deposited directly into the unfortunate shrimp’s tissues as they are known to do.
White planarians are classified as Procotyla fluviatillis. These critters are fiercely predatory, eating small worms, crustaceans, daphnia, and even other planaria. Procotyla will attack anything small that comes within reach, including shrimp eggs, shrimplets, and even adult shrimps. Although they typically occur in fewer numbers than Dugesia planaria, these pesky critters can still do a lot of damage to the peaceful shrimp that share your betta fish’s tank.
How to get rid of planaria worms
So, you can see that you really don’t want an infestation of planaria worms in your tank. Unfortunately, both types of these persistent pests are extremely resilient, and they can be incredibly challenging to eradicate.
Emptying the whole tank and starting over won’t shift the worms. They will simply reappear and quickly multiply to reinfest your aquarium. Changing the water temperature doesn’t work either. In fact, research has shown that planarians can survive in refrigerated conditions with no food at all!
Copper treatments can be effective against planaria worms, but they will also harm shrimps and snails. However, if you don’t have invertebrates living in your community, dosing the tank with a copper-based medication could do the trick. As with any form of chemical treatment, read and follow the manufacturer’s directions carefully, and never exceed the recommended dose.
Betel nut palm extract
Betel nut palm extract is a herbal treatment that is highly effective against planaria and will get rid of the worms without harming your shrimp and fish. You’ll find betel nut palm extract as the active ingredient of a herbal product called No Planaria, which you can buy online at this link.
Remember that you will need to give your aquarium a thorough overhaul and a deep-clean with an aquarium vacuum cleaner to get rid of all the dead and dying worms once the treatment has concluded.
Chemical worm treatments
Because planaria problems can be caused by just a few worms that are tricky to spot, getting rid of them is tricky. For that reason, chemical treatments are usually the preferred method of eradicating the pests.
However, chemicals can be very harmful to fish, plants, and invertebrates, so you need to be absolutely certain that planaria are the problem. If you’re in any doubt, capture a couple of the worms in a planaria trap and ask your local fish store or veterinary practice to confirm the species of parasite you’re dealing with.
Once you know that you definitely have planaria worms in your tank, it’s vital that you thoroughly research the chemical product that you use to make sure it’s safe for your fish and other livestock. In particular, remove invertebrates from the tank before you treat the water. Also, some species of bottom feeders, scaleless or Metynnis fish species, may also be highly sensitive to worm eradication treatments, so we recommend that you remove these fish from your tank before treatment.
Always follow the manufacturer’s guidelines precisely when using chemical treatments in your tank, as overdosing could kill your fish. For your own personal safety, be sure to wear gloves when handling chemicals.
The most effective chemicals for treating planaria worms contain Trichlorfon, which is a powerful neurotoxin. However, we recommend that you ask for advice from your vet or local fish store when choosing a treatment for your fish tank.
Treating sensitive fish
As mentioned, it’s potentially very dangerous to use chemical treatments in a betta tank that contains sensitive fish species, so you should remove them and rehouse them temporarily until the main aquarium has been treated.
But what do you do if a sensitive fish or your betta has one of these fluke worms attached to it?
The easiest way to remove the worm is to treat the fish with a quick saltwater dip or bath. To find out more about giving your betta fish a salt bath or dip, read this detailed guide.
Before returning the fish to the quarantine or main tank, take a pair of blunt tweezers and gently remove the weakened worm from the fish’s body.
Panaria worms can be a real nuisance in your fish tank, especially if you keep shrimp. To effectively get rid of the worms, you’ll need to use a chemical treatment, but be sure to remove any sensitive species of fish first.
Once treatment is complete, give your tank a thorough deep clean by vacuuming the substrate. In the future, be sure to keep your aquarium clean and free from fish waste, leftover food, and general detritus that can provide food for the worms.