Aquarium, Fish Parasites, Worms; Planaria, Nematodes, Detritus, Anchor

 

By Carl Strohmeyer-PAMR 40+ years experience

Updated 6/19/23

FISH PARASITE & NON PARASITE WORMS;
In Aquariums & Ponds
The Index below index breaks down the Worms into their three Phylums:
*Platyhelminthes, *Nematoda, & *Annelida
As well as information about Feeding Worms & Anchor Worms, which are not worms, rather copepod crustaceans.

• Platyhelminthes (Trematodes, Flukes, Fish Lice, Flat worms, Planaria)
• Treatment of External Flukes, Planaria, etc
• Nematodes (Round Worms); Including Camallanus, Capillari
• Treatment of Internal Nematodes (& some Internal Trematodes)
• Suggested Treatments/Preventatives for Both Internal/External
• Annelids (Segmented Worms), Detritus Worms
• Anchor Worms
• Treatment of Anchor Worms
• Hydra
• Feeding Worms including:
• White Worms
• Microworms
• Walter Worms
• Vinegar Eels)

Basics, Identification, and TREATMENT in Aquarium and Pond Fish.

Readers should note that ALL these parasites are INTRODUCED, whether by a fish directly or by an intermediate host such as a snail.
If you have had a certain fish for over a year, with no additions or possible intermediate hosts in the last six months, chances are you do not have one of these worms infestations listed. So always look for identifiable evidence of actual worms, and lacking these, utilize all circumstantial evidence to confirm otherwise, including the chances of introduction.

Otherwise, follow any circumstantial evidence that may be pointing to other copycat symptoms which may include internal Aeromonas infections, Ichthyophonus, osmoregulation issues, simple aging/genetics/earlier life trauma that injured internal organs, or quite often poor diet which can cause eventual liver & kidney damage as well as making a fish more susceptible to intestinal Aeromonas infections (which can present in feces like parasitic infections).
The bottom line without introduction in the last few months; what many might think is an internal parasite problem is very likely not and is a much more common Aeromonas bacterial infection (which is all around from the soil to your substrate and does not need introduction into the aquarium) or also quite possible, with the plethora of well marketed fish foods with poor energy levels and poor fiber contents, a nutritional issue.

Suggested Diet for CORRECT energy and fiber levels/content:
Clay Neighbor's AAP Custom Fish Food

Information is included about non parasite Detritus Worms (commonly seen when an aquarium is cleaned or in aquariums with high bio loads and is an area with much confusion especially on the internet and often mis-identified as PLANARIA (Freshwater). More about Detritus Worms further into the article.

Information about: The Truth about Planaria in Aquariums

For information about "Whirling Disease" caused by the myxozoan parasite "Myxobolus cerebralis", please refer to this related article from "Aquarium/Pond Answers:
Whirling Disease (Myxobolus cerebralis) in Fish

Before any aquarium/pond fish treatment it is important to know all the steps as often treatment is much more than dumping medication into an aquarium.
Please read this article before ANY aquarium treatment regimen:
Fish Diseases | How to Treat Sick Fish

PLATYHELMINTHES:
(Monogenea, Trematodes/Flukes, Planarians)

Platyhelminthes consists of the unsegmented flatworms, which include both free-living and parasitic species.
These worms have bilateral symmetry, and can move by using layers of muscle or by gliding along a slime trail using cilia.
Flatworms lack a circulatory system and complete digestive system, instead flatworms absorb nutrients through their skin and excrete wastes using specialized "flame cells".
*Flame cells function like a kidney, removing waste materials.

A few flatworms have primitive light-sensing "eyes" that allow them to move either towards or away from light, while other species have different types of sensors on their bodies, including chemical, balance, and water movement receptors. Most species of flatworms reproduce both sexually and asexually.

The trematodes belong to the Animal Kingdom Phylum Platyhelminthes, and are commonly referred to as flukes.
Trematodes usually have flattened bodies, a primitive digestive system, suckers for attachment to their hosts, and are hermaphrodites (an organism that possesses both male and female sex organs).

The Monogenea are the class ectoparasites that infect fish.

Planaria are both marine and freshwater and can be parasitic, but this is generally rare and the few that are, generally are parasitic toward corals, eggs or other stationary "victims".
See the section on Detritus Worms for more about Planaria since these are all too often confused with Detritus worms even though a completely different Phylum of worms.

INTERNAL TREMATODES:

Internal Flukes generally use intermediate hosts such as snails or other mollusks. The eggs must get into water in order to hatch and be able to infect their first host, a freshwater snail. The fluke develops in the snail and then burrows out to seek the second host which is a freshwater fish. Many species of snail and fish may carry these internal flukes.

- Here is a dissected fish displaying a serious internal Trematodes infection.

GILL FLUKES:

Gill flukes (Dactylogyrus) will appear on the gill filaments as tiny dark spots 0.04-0.08 inches (1-2mm) long.
Gill flukes can infect freshwater and saltwater fish and are found on fish from the wild as well as farmed fish.

These parasites attach to the gills of the fish and feed on mucus, epithelial cells (cells that line the inside of gills and perform the tasks of secretion, absorption, protection, and transcellular transport), and blood from the host.

The pictures above display first a standard microscopic slide of an isolated gill fluke and then to the right a Scanning Electron Microscope view of a gill fluke attached to gill filaments.

It is noteworthy that 100% positive identification with the naked eye is impossible.
Other than scraping the gills (which can be fatal to the fish) and then preparing a slide, your best recourse is an "educated guess" based on redness in the gills (which can be other issues too such as ammonia poisoning burns), and scraping (flashing) of the fish against objects in the aquarium or pond in the area of the gills.
In fact in the absence of this "flashing", odds are the redness is bacterial (often Columnaris) or inflammation from ammonia poisoning (past or more likely present)

More about Gill Flukes;
Much of the mucus being produced by the fish is in response to the physical injury caused by the parasites.
Damage is physical and inflammatory, with secondary bacterial infections such as septicemia. Small or weak fish may die from the stress of acute infestations.

Gill flukes reproduce via eggs that drop away to hatch in about 2 to 4 days depending upon temperature.

The hatchling Dactylogyrus is ciliated similar to a paramecium. Once a host is found the water-borne Dactylogyrus larvae has eye spots that enable it to swim away from light and burrow into the fishes' gill cover as the fish respires.
From my experience in a healthy aquarium or pond, even if one or two fish in the aquarium/pond have a large enough parasite infection to be irritated, if the larva fails to find a host, it dies.

However in poorly filtered and/or crowded ponds or in particular aquariums, these conditions increase the likelihood the larva will find a host. Once attached, it may take a week to mature and start producing eggs.
The adult Gill Fluke is assumed to only live 5-10 days.
Improving filtration and over crowding is as important as treatment.

With larger ponds, generally isolating the fish in a tub or small "play pool" is all that is necessary for treatment, assuming crowding and filtration is not a problem or improved.

Common aquarium carriers of gill flukes include: Plecostomus, Otocinclus, Corydoras, Koi, Discus, Characins, livebearers (Poeciliidae), some tetras (Characins) and Barbs (Cyprinidae), and Elephant Nose (Gnathonemus petersi).

For more about Monogeneans Flukes, which are a group of parasites best described as flatworms but are now considered a different class from Trematodes, please see these articles:
*Monogenean Parasites, Marine Fish
*Monogenean Parasites in Fish

FISH LICE (Argulus):

These are often round, flat and green.

They are similar in treatment to flukes and anchor worms. These can be physically removed with tweezers, and then the wound treated with Mebromin, hydrogen peroxide or even Neosporin followed by a 30 minute Methylene Blue Bath.
Reference: Fish Baths; Basic Ingredients, Methylene Blue

MARINE FLATWORMS:
The Acoel flatworms commonly observed are “Redbugs” or “Red Planaria”, of which the genus Convolutriloba is a member as in the picture to the left of Convolutriloba retrogemma.

While Convolutriloba retrogemma are often blamed for coral attacks, in reality this is rare. Rather, they breed rapidly and reproduce either sexually, laying eggs or by the asexual processes of fission/ budding where the worm simply splits up, producing a bud that forms a new worm.
Therein lies the problem: the flatworms crawl along the coral in search of food and, as they rapidly multiply, they block the coral's light as well as hamper nematocyst capture of the coral’s prey. The coral is thus deprived of symbiotic nutrient nourishment, as well as planktonic food, and slowly starves to death.

The use of "Reef Dip" or a freshwater dip of corals or similar is the best prevention for these flatworms.

Where to purchase: *SeaChem Reef Dip

Treatments for External Flukes or Worms (including Flatworms/Planaria):

• Clout/Dylox
  Clout, Dylox (AAP Dyacide) and other "in tank" treatments are often more effective when accompanied by baths or dips, as well, if a parasite such as a camalanus worm is exposed, treatment is often more effective.
  
  Where to purchase:
  AAP Dyacide (Dylox)
  
  For marine applications, I generally will treat twice with a water change and carbon treatment in between.
  ALL invertebrates should be removed during treatment (Corals, Shrimp, Anemones, etc.).
  Prior to re-introduction to the treated aquarium, all corals should be dipped in pH stabilized freshwater for 25 to 45 seconds.
  A standard dose of Potassium Permanganate or AAP Dyacide or Clout can be added to this dip for extra measure.
  
  This can also be used for nematodes, camalanus worms, or internal protozoans; although sometimes multiple dosages may be required.


• PraziPro
  This can be used as either a bath (as well as mixed with Methylene Blue) or 'in-tank. treatment.
  This is highly effective when used as directed for external parasites
  Mild effectiveness for internal parasites
  
  *Methylene Blue from AAP
  
  
• Trichlorfon


• AAP Potassium Permanganate

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NEMATODES:
(Round Worms)

Nematodes, also known as Roundworms, are a very common phyla of animals of which there are many parasitic forms. Nematodes are one of the simplest animal groups to have a complete digestive system, with a separate orifice for food intake and waste excretion unlike the Trematodes mentioned above. Reproduction is usually sexual and males are usually smaller than females.

Parasitic Nematodes can have quite complicated life cycles, moving between several different hosts or even locations in the host's body.

If the Nematode has a direct life cycle, then it does not need an intermediate host and infection can spread directly from one fish to another by means of a fish ingesting of eggs or larvae.

If the Nematode has an indirect life cycle the nematode eggs or larvae enter an invertebrate intermediate host (such as copepod, tubiflex worm, or insect larva) or a fish intermediate host (these fish are then consumed by larger carnivorous fish) prior to being eaten by or entering the final host fish.

Indications (Diagnosis) of Nematode Infestation:
A method of diagnosing a nematode problem is generally just a guess. This is particularly plausible when a fish is eating regularly yet continues to lose weight, metabolizing body musculature to stay alive.
This is usually seen as thinning along the back on either side of the dorsal fin. This often results in a well-fed fish starving to death.

White feces can also be an identification tool, however this can be misleading as to a true Nematode (worm) infestation, as long thin white feces along with bloating are just as often an indicator of a bacterial infection; generally Aeromonas or possibly a digestive issue.
This can also be an indicator of a combination bacterial (again Aeromonas) and protozoan Flagellate infection, usually Hexamita.
Loss of appetite along with the other mentioned symptoms (such as thick white feces, along with some bloating on one side or both of the fish) can also be an indicator of a Nematode infection, especially a Eustrongylid nematode infestation.

Much More Information:
Gram negative, Aeromonas Infections in Fish

Generally a more positive identification of internal Nematodes is a thread like worm protruding from the anus.

True identification begins with a microscope (& often requires a necropsy of the fish after death).
Nematodes are smooth, cylindrical, relatively long worms, which distinguishes them from the flatter, segmented tapeworms and from the wider and shorter Monogenea Flukes.

Here is a list of some other general symptoms of nematode infections (besides the above already mentioned symptoms):

• Body Hemorrhaging
• Lumps or nodules on outer body (epidermis)
• Bloated or the opposite, wasting of the abdomen (the fish may continue to eat or show otherwise normal behavior).
  It is noteworthy that bloating in particular is generally a better indicator of a gut infection such as caused by Aeromonas Bacteria and/or a poorly functioning digestive system (which could also be the result of poor fish osmoregulation)
• Cysts, Inflammation, or Granulomas

A Few Common Nematodes:

Capillaria/Capillari.

These are probably the most common nematode due to the relatively non-complex life cycle and ease of transmission, as Capillaria spread from one fish to another by ingestion of infective larvae that live in the intestines of cichlids such as angelfish, discus, gouramis, tetras, cyprinids (and some other fish as well).
This is often referred to as "Gourami Disease" due to the frequency of infection in Gouramis

Symptoms common to this particular nematode include a bulge in the lower abdomen near the vent, or Capillari worms protruding from the anus.

Eustrongylid nematodes.

These are found in muscle within the body cavity or encapsulated on the liver and other organs. These nematodes can affect a number of different species such as guppies, gar, danios, angelfish and other cichlids.

Affected fish typically have bloated abdomens (similar to dropsy of bacterial origin), as these nematodes often migrate into the body cavity and can be quite large.
Unfortunately the treatment of these Nematodes usually fails due to the location of the larvae within the coelomic cavity or in the muscle of the fish, which is often misdiagnosed as bacterial Dropsy leading to the somewhat misleading statements that “Dropsy is un-treatable” when in fact the problem was NEVER Dropsy!

Reference: Dropsy in Fish

Camallanus Nematodes.

These infect the gastrointestinal tract of live-bearers, cichlids and other species of freshwater fish.

Symptoms (but not necessarily proof of infection):

• Usually, the first CLEAR indication of infection is a red worm extending from the anus of a fish (sometimes mistaken for feces).
• Scoliosis; Lateral curvature of the spine
• The lower part of the fish' body is hollow and wasted
• Parasite infested fish show very slow or no growth, as parasite is taking the food.
• Fish is fading away, looks as if it is starving to death.

The life cycle of Camallanus worms passes through three phases;

1. A free-living stage
2. A series of molts during which time the worms infect an intermediate host (crustaceans such as Cyclops and Gammarus)
3. Then another molt that takes place in the final host/fish.

If the intermediate host crustacean is eaten by a fish, then the third-stage larvae becomes active and will start feeding again.
After two more molts, it will become a sexually mature male or female adult worms.
These are the distinctive red worms aquarists see protruding from the vents of infected aquarium fish.

One exception is the Camallanus cotti which has the ability to skip this stage, if a suitable crustacean host is not available. However there still needs to be a pathway to infection, which still often can rule out reinfection. Consumption of an infected fish by a tank mate or ingestion of feces produced by infected fish are possible modes of continuing the life cycle and thus reinfection. Removal of dead fish and other methods of consumption along with isolation and quick clean up of any and all feces should break this life cycle from my experience.

TREATMENTS for Internal Trematodes and Nematodes:

Before you treat, I suggest reading this article also from the "Aquarium/Pond Answers library:
Fish Diseases | How to Treat Sick Fish

The above article is very helpful in that often even milder mediations are much more effective when ALL PARAMETERS are spot on.
In particular, I have seen the relatively mild Metronidazole/Praziquantel combination work well for Camallanus worms when parameter are spot on (this includes a balanced Redox by keeping oxidative stress as low as possible) and not work at all when these are not.
This why we need to be careful with anecdotal advice when it comes to statements that "Metronidazole/Praziquantel will not work", as when we dig deeper as per my long time experience with fish treatments, we will often find that there is a reason the treatment failed, and it was not the medication.

• Metronidazole is a mild treatment parasitic worm treatment that is most effective for single cell parasites such as flagellates (examples include Giardia), but it can be even more effective when combined with SeaChem ParaGuard in tank and/or then used as a medicated food soak combined with Praziquantel (do not use ParaGaurd as part of the fish food soak).
  The use of Metronidazole has the added benefit in that it is effective for anaerobic internal infections, common to the gut.
  
  Reference:
  *Aquarium Medications; Food Delivery of Medications
  *What Are the Treatments for Intestinal Parasites in Humans (while not aimed at fish treatment, much more research goes into human worm treatment, so still worth a read)
  
  Recommended Product Sources that support this FREE Information and the Aquarium/Pond Keeping Hobby::
  *AAP Metronidazole
  *AAP ParaGuard


• Praziquantel; this product works in part by paralyzing the parasites, thus allowing the host to more easily shed the parasite both internally and externally.
  Generally only one treatment is needed (if fed, two to three times in one day), although re-treatment 5-7 days days later of a product containing Praziquantel is required.
  Praziquantel along with Metronidazole are a couple of the safer medications you can use for your fish to treat parasites, both internal & external (& more effective when combined).
  
  
• AAP General Cure
  General Cure (which contains Praziquantel, Metronidazole) can be used as a medicated fish food soak for internal parasites.
  Jungle/Tetra Parasite Guard is similar (it contains Praziquantel, Metronidazole, Acriflavin, Diflubenzuron).
  Of the two, General Cure is the better choice since Acriflavin & Diflubenzuron are intended only for external parasites (of which this is the better product for external parasites/worms).
  
  General Cure can be used as a medicated fish food soak by using 1/2 a packet for an average 60 gallon bio load medicated fish preparation. Fish food should be soaked for 15 minutes. After soak, pour entire contents into aquarium
  
  Recommended Product Source that support this FREE Information and the Aquarium/Pond Keeping Hobby:
  *AAP General Cure


• Levamisol Once one of the more popular treatments for nematodes, but increasingly harder to find due to many safety concerns which includes the fact it is much more dangerous than others listed here when over dosed or even used normally as it can cause serious liver and blood issues. Even in doses needed to treat internal worms, "Neutropenia" may result which then results in the fish being more susceptible to bacterial infections.
  Levamisol is best used as part of a blend, such as in AAP Discomed where overdosing is nearly impossible since it is part of synergistic blend, otherwise use it as a treatment as a last resort due to the problems it can cause with the fish immune system, especially if over dosed accidentally.
  AAP Discomed contains Levamisol, Neomycin, Magnesium Sulfate, NaCl, & Piperazine
  
  Recommended Resource: AAP Discomed (Fish Food Soak) This is the strongest yet safest internal parasite fish food soak medication available anywhere! This is a product NO SERIOUS AQUARIUM KEEPER SHOULD BE WITHOUT IN THEIR ARSENAL!
  
  See this article for use and cautions:
  Aquatic Medications #3; chemical and parasite treatments
  
  Treat with Levimisol once followed by a water change and treatment in 3-7 days. Treat a third time after 1-2 weeks following the second treatment.
  Be careful, as Levamisol can kill many worms quickly, which with most internal nemtode infections is not an issue since they are not generally widespread. HOWEVER with use for widespread worm infestations, this can be a problem which is why this should NEVER be used to kill Detritus Worms (often misidentified as Planaria)
  
  Here is a source for Levamisol:
  https://www.inkmkr.com/Fish/ItemsForSale.html


• Piperazine An especially good choice for Capillari and a safer choice than Levimisol or Fenbendazole if you can find it. It is also more effective than Praziquantel.
  The reason Piperazine is safer is that it works via anthelmintic action (used to expel or destroy parasitic worms in the gastro-intestinal tract).
  The mode of action is generally by paralysing parasites, which allows the host body to easily remove or expel the invading organism.
  For this reason, Piperazine is gentler on the fish and aquatic environment.
  Reference: Aquarium Medications Part 3; Piperazine
  
  Recommended Resource for Fresh Piperazine:
  *AAP Piperazine/Pipzine
  *AAP Discomed (Fish Food Soak)


• Fenbendazole; Commonly sold as a dog de-wormer and has a wide range of internal worms it will kill. It works by interrupting the parasites’ cellular transport and metabolism.
  Fenbendazole can be mixed with fish foods, but often flavor enhancers such as AAP Garlic Guard are needed to hide this medication so that fish will accept the food "spiked" with Fenbendazole.
  Do not combine with Praziquantel
  
  Do not use if your fish has any bleeding issues, as Fenbendazole can inhibit red blood cell production


• Combinations such as the above mentioned AAP General Cure that have Metronidazole as an ingredient as this medication is often effective for secondary bacterial infections such as Aeromonas and even better for possible Hexamita infestations of the gut, as witnessed in a white feces diagnosis where the aquarist is unsure of whether this is a worm or Aeromonas/Hexamita infection.
  Adding Neomycin to the Fish Food soak may help with secondary infections and/or gut infections while adding Nitrofurazon or even stronger AAP Spectrogram to external "in-tank" or hospital/bath treatments can help with secondary infections, especially Aeromonas infections.
  
  Recommended Product Sources:
  *AAP Discomed (contains Levamisol, Neomycin, Magnesium Sulfate, NaCl, & Piperazine)
  *AAP Yellow Powder- Premium Nitrofurazone
  *AAP Spectrogram; Kanamycin/Nitrofurazone Wide Spectrum Combination
  *AAP Neomycin


• Epsom Salts; While not a treatment, the use of pure Epsom Salts (do not use scented products such as Lavender Epsom Salt) can help with passage of the parasite when used in a bath and or a fish food soak.
  
  For a fish food soak (along with medications such as General Cure), I suggest 1/8- 1/4 tsp of epsom salt along for every ounce of food prepared.
  
  The addition of AAP/SeaChem Garlic Guard to this fish food preparation can further help with palatability.
  Recommended Product Source:
  *AAP/SeaChem Garlic Guard
  

For BOTH Internal and External Nematode/Trematode Treatment

• Medicated 30 minute baths using Methylene Blue, Aquarium Salts, as well as the antibiotics such as Metronidazole or Nitrofurazone at double normal recommended tank strength; This will aid in absorption of medications and osmoregulation that is VERY important, especially with internal parasite infestations which are difficult to treat even with strong medications.
  The Methylene Blue will be absorbed and aid in oxygen delivery although it is only mildly effective against the parasites, Methylene Blue aids in the fish’ general health.


• A good follow up treatment as well as preventative which also improves fish immune resistance via improved Redox Balance (lowering oxidative stress) would be an AAP Medicated Wonder Shell.
  The AAP Medicated Wonder Shell is also a good part of a everything but the kitchen sink type treatment when it is not clear whether the problem is nematodes or an internal gut infections
  
  If a medicated fish food soak is being used, the Medicated Wonder Shell would also be useful as an in-tank treatment to fight infection and improve fish immunity.
  
  Product Resource:
  AAP Medicated Wonder Shells


• Berberine (Oregon Grape Root Powder): While a new use in the aquarium hobby, growing evidence for the use of Berberine best found in Oregon Grape Root is growing in human studies. Since more funding is available for human studies, this often makes these studies more valuable and accurate.
  "Berberine has demonstrated significant antimicrobial activity against a variety of organisms including bacteria, viruses, fungi, protozoans, helminths, and chlamydia. Currently, the predominant clinical uses of berberine include bacterial diarrhea, intestinal parasite infections, and ocular trachoma infections."
  Reference: Berberine; US Library of Medicine
  
  Another benefit of the use of Oregon Grape Root as a source of Berberine is this herbal treatment can work with many other standard treatments such as Metronidazole to improve effectiveness.
  
  Current suggested use is 400 mg of power per 10 gallons of water and used as a additional treatment in aquariums and fish baths, not the sole treatment.
  
  Further Reference: Aquarium Medications Part 4; Oregon Grape Root

Recommended Product Sources that support this FREE Information and the Aquarium/Pond Keeping Hobby::
*AAP Yellow Powder- Premium Nitrofurazone
*Methylene Blue from AAP
*AAP Medicated Wonder Shells

How to perform a Medicated Fish Bath:
*Medicated Fish Baths; Dips, Swabs

Salt is advised not only in the baths at 1-2 teaspoons per gallon, but also in the display or quarantine tank at 1 teaspoon per gallon to 1 tablespoon per 5 gallons as this will also aid in mucous generation and the movement of fluids inside the body cavity (osmoregulation).
Correct Calcium Levels are also important for osmoregulation that will aid the fish in “battling” a parasite infestation (especially internal).

Also see these article for more about medicated baths & fish quarantine:
“Aquarium Disease Prevention; Quarantine, Baths”

Prevention is the BEST treatment for Nematodes, Marine Flatworms, and Flukes, especially Internal Nematodes

This is accomplished by regular water changes, the purchase of fish from a known quality resource, removal of the final host (in the case of Eustrongylid nematodes; birds and pond sanitation), or any intermediate hosts (tubiflex worms or other oligochaetes).

It is noteworthy that many (if not most) fish farms are located OUTDOORS, so the spread of nematodes via intermediate and finals hosts is easier than one may think. Knowing your source for your pet fish is very helpful as often many internal nematodes will not show symptoms in fish for over 30 days after arrival in your aquarium.

A final note as to treatment of nematodes in particular is that nematode infestations are generally internal, making treatment and medication “delivery” very difficult. More so with Eustrongylid nematodes since they are found in difficult to deliver mediation internal body locations.
My point here is, hopefully one can start treatment early or prevent an infestation altogether, however from my experience this is not a “real world” expectation as I have often failed to detect and treat with success (assuming it was treatable in the first place), so one should not be too hard on failures in treating internal Nematodes, as I have had my share of both successes and failures even under the good care.

Annelids “Segmented Worms” - Including:
DETRITUS WORMS

The annelids are the phylum of segmented worms which include earthworms. Most annelids are NOT purely aquatic in fresh water; the annelids found in freshwater are all oligochaetes (which means "few-bristled") and are not very important in the freshwater ecology as are their marine cousins, the polychaetes (which means "multi-bristled").
All the oligochaete worms are hermaphrodites (an organism that posses both male and female genitalia) and many are nearly microscopic.

Detritus Worms (from the group of worms called Oligochaetes, sub group naidid worms) are often misidentified in the aquarium hobby as Planaria without close inspection by many internet articles such as about.com.

Many of these worms are accidentally introduced by live plants, gravel (especially in the case of common Detritus Worms) live fish foods, and even brought in with fish transfers.
(Click picture to enlarge)

Many not familiar with Detritus worms will label these as everything from midge larvae, Planaria, to baby earthworms, of which none is true. They are very common and most often seen during vacuuming and other cleaning procedures.

These worms generally are not a problem and often go un-noticed living in the gravel aiding in breakdown of wastes, however high numbers of particular species can indicate low oxygen levels, cloudy water, poor Redox and low filter productivity.
This very often suggests some degree of pollution caused by poor cleaning procedures, over crowding, over feeding and poor filtration.

When the population explodes these worms often leave the gravel and cling to the sides, usually close to the surface as oxygen depletion due to the cumulative affects of increased organic mulm (often resulting with pH/KH drops, higher nitrates, poor Redox Balance), cloudy water and simply too many Detritus worms. This then drives them from the oxygen poor gravel where they normally hide/exist.
It is when these worms are crawling up the sides that most aquarium keepers take note, often not realizing that these worms have been present for some time living quietly in the aquarium substrate before a population explosion and often subsequent oxygen depletion drives them into the open.

Do NOT make the mistake of treating with Levamisol to rid your tank of Detritus Worms (aka false Planaria) as so many forums and websites advice.
I know for a fact that the die off can kill off many fish and that simply taking care of the cause of the worm population "explosion" will remedy this issue!!!

Please reference these sources for even more identification (and further information so as to dispel the internet aquarium myth that these are Planaria):
Detritus Worms/Planaria in Aquariums
The above article is THE article to read on the subject!

Other Reference:
*Aquatic Worms

“Detritus Worms" include these:

As stated earlier, control of these detritus (composting) worms is brought about by good vacuuming procedures, proper feeding, good filtration, lowering bio load, and addition of fish that will eat these.

This is a Planaria (a flat worm, not an Annelid)!
(click to enlarge)

ANCHOR WORMS:

Anchor Worms as seen to the left are a genus of copepod crustaceans (Species Lernea) that are parasitic to freshwater fish, especially coldwater fish often raised in ponds such as Goldfish.
I also have personally caught Trout that have been covered in Anchor Worms, but it is noteworthy that these trout were in a small, man made lake that by late spring is too warm for Trout to live in.
The point about the trout is applicable to the many anchor worm infestations I have dealt with in goldfish, in that it was much more common in warm or warming months where water temperatures are higher than is best for goldfish, @ 80F or higher.

The Anchor Worm is not always noticeable as pictured here, often it starts out as a small red sore. These red sores then multiply followed by small thread like protrusions that are the anchor worm.

Other common symptoms include frequent rubbing/flashing, inflammation on the body of the fish, and generally lethargy of the fish such as sitting on the bottom or floating on the surface of the water.

TREATMENT:
Best treatment is to use tweezers to remove the worm from the fish.
The fish should be gently cradled in the palm of your hand so as to not injure the fish as a net can. After removal, the wound SHOULD/MUST BE treated/swabbed with Merbromin/AAP Wound Control (Best to prevent an infection), Methylene Blue (2nd choice), or Hydrogen Peroxide (3rd choice).


If the Anchor Worm cannot be removed (or you are uncomfortable doing so), this is especially true with very small anchor worms, a direct swab of 50% water Potassium Permanganate & water directly on the worm should be performed followed by a rinse then a swab with Merbromin (AAP Wound Control).

With either procedure, a bath should also follow that consists of AAP Nitrofuracin Green, OR Methylene Blue, Salt, Nitrofurazone, & possibly Metronidazole.

Recommended Product Sources that support this FREE Information and the Aquarium/Pond Keeping Hobby::
*AAP Wound Control (Merbromin)
*AAP Nitrofuracin Green- Full Spectrum Treatment
*AAP Yellow Powder- Premium Nitrofurazone
*AAP MethyBlu PREMIUM Methylene Blue (Best version)
*Kordon Methylene Blue from AAP
*AAP Potassium Permanganate (Clear Water)

For serious infections and to prevent reinfestation, an in tank treatment with AAP Dyacide or Clout (Dimilin is similar), OR Pimpzine OR a Super Ich Plus (or ParaGuard, but not as strong)/Furan 2 combination can be used, OR General Clear, OR PraziPro (this is in order of strength).

AAP Dyacide or Clout (Clout is no longer available) are about the only treatments that will kill the Anchor worms while still actually on the fish, otherwise most medications kill Anchor Worms in the free swimming stage.

If a secondary infection is also present (which is common), such as red sores, a combination of AAP ParaGuard and Triple Sulfa OR AAP Furan 2 is often the best choice (beside the before mentioned physical removal and baths)

As part of the lifecycle, the female anchor worm will release her eggs into the water when they are about to hatch into free swimming larvae. These larvae will swim about for up to a week looking for a fish to attach itself to. If they don’t attach themselves in this period of time they will die off. So interrupting this is generally essential for a full "cure".
This means healthy aquarium conditions, including optimizing ALL water parameters along with water changes.
A medicated fish food using your current fish food soaked with AAP Discomed may help further along with AAP Pipzine, Prazipro or General Cure in the aquarium (Pipzine being the first choice).
More about optimum aquarium care: AQUARIUM DISEASE PREVENTION; Steps to a Healthy Aquarium & Sick Fish

Beware of non aquarium professionals often in social media forums that will recommend herbal products such as Microbe-Lift Herbtana & Artemiss. There are no published ingredients from these discount seller products and more importantly these products negatively affect your aquarium's Redox balance which would be the last thing you would want to do with a fish suffering from an Anchor Worm infestation especially one that is accompanied by sores and/or Septicemia.
Reference: Aquarium Medications Part 4; Microbe-Lift Herbtana & Artemiss

As well, beware of discounters such as Amazon selling products containing diflubenzuron (Dimilin).
With diflubenzuron, fish have been shown to accumulate diflubenzuron at a rate 76 and 99 times greater than the water content in the gills and liver which can affect long term fish health.

Recommended Product Sources that support this FREE Information and the Aquarium/Pond Keeping Hobby:
*AAP Dyacide (Dylox)
*AAP Pipzine
*AAP Discomed
*AAP Super Ich Plus
*AAP ParaGuard
*AAP Yellow Powder- Premium Nitrofurazone

A follow up in tank treatment with a Medicated Wonder Shell can be helpful too, regardless whether a previously mentioned strong in tank treatment was used or not.

Where to purchase: *Medicated Wonder Shells

HYDRA:

These small invertebrates are closely related to jellyfish and coral, which prey on small fish, shrimp, etc. While Hydra appear quite small and undefined in shape, they are simply small adult predatory animals.
Hydra have a tubular-like physique and measure just about a few millimeters. They possess one sticky foot on one side of the lower part their body, with several tentacles forming the other end of their body.
These tentacles have stinging cells which are capable of immobilizing their prey.
Hydra can take out prey close to their own size and their quick reproduction allows for the quick spread of Hydra.

Generally Hydra are accidentally introduced into an aquarium by many different means, often without the the unsuspecting aquarium keeping even knowing.
Plants or other bio introductions from a pond sources are common sources of introduction.

TREATMENT FOR HYDRA:
Many have successfully used fish such as blue or gold gouramis as well as paradise fish and sometimes mollies too to eat hydra (although this often does not completely rid your aquarium of these pests).

Generally chemical treatment is the best method of treatment, but can treatments that are effective generally will kill shrimp, snails, and similar invertebrates.
Be careful of using Dog wormers as is often suggested, as while these can be quite effective, these also can remain toxic to your aquarium environment.
Better is something intended for the aquarium environment that degrades quickly such as Clout or AAP Dyacide (unfortunately Clout has been discontinued).
Thorough water changes after use is also a must to keep down a possible spike in the nitrogen cycle.

Resource: *AAP Dyacide (Dylox)

WORMS USED AS FISH FOOD

Annelids:

Whiteworms (Enchytraeus albidus):
These are worms commonly used in feeding for larger fish; for instance, Gouramis and Cory cats love Whiteworms. Microworms (which are Nematodes not Annelids as are Whiteworms) are used for fry.
What we typically refer to as a "white worm" in the aquarium hobby is a segmented round worms (Annelids) that are closely related to the earthworm from the family enchytraeids. Whiteworms are an excellent food source for many amphibians and other aquatic creatures.

These worms can reach over 1 cm or more long. They are NOT a parasite danger to fish or other inhabitants of aquariums and are often seen wiggling up the sides or even at the surface. Whiteworms are basically a worm of de-composition and can multiply rapidly when over feeding is a problem. At this point the biggest danger is oxygen depletion from over population of these worms and a good vacuuming is in order. Many a customer has called or written me about these worms worrying that they have a parasite problem when in reality these worms are good for composting and are at worst an indicator of too much decomposing food and other organic debris.

Grindal worms

Nematodes

MicroWorms:
All the worms that fall under the popular term of Microworms are Nematodes (roundworms) and include Vinegar Eels, and Walter Worms. Microworms (Panagrellus Redivivus) are non parasitic and small (0.5 - 1.5 mm.) worms, which make excellent supplementary live food for fry which are either too big for infusoria or have outgrown the infusoria stage.

Walter worms:

Walter Worms are about half the size of the Microworm. These are recommended for feeding the very smallest fry. Walter worms generally live in the water longer than the Microworm.

Vinegar Eels

Vinegar Eels are also a nematode are readily cultured in large numbers, provided certain procedures are followed. These worms (also nematodes) are a little smaller than micro-worms, a great size for most baby fish. The worms must be grown in natural cider vinegar that has not been chemically treated to inhibit the growth of bacteria or yeast upon which the worms feed. Advantages of Vinegar eels is they do not breath oxygen so don't create any problems in the fish tank, live a long time in the aquarium, and swim in the water column and stay towards the surface.

References:
*Camallanus (Camallanus cotti & C.lacustris)
*The Worms
*Whiteworms
*Microworms (Panagrellus redivivus)
*Platyhelminthes
*https://www.inkmkr.com/Fish/CamallanusTreatment/ *University of Florida; Nematode Infections in Fish

Other Recommended Aquarium Information/Videos:

The most effective medication BAR NONE for the treatment of Columnaris in an aquarium when used as part of the four step program of Columnaris treatment.


AAP Yellow Powder- Premium Nitrofurazone

YouTube; How to: 4 Steps Columnaris Treatment Fish Bacterial Infection

This video goes over the basics of the full four step plan of properly treating Columnaris in aquarium fish and is a compliment to a FULL reading of this article.

*The article below is a MUST READ for anyone interested in moving from basic aquarium keeping to more advanced aquarium keeping, including better Redox Balance:

Aquarium or Pond UV Sterilization; Level 1 Sterilizer Use

Also for level 1 capable UV Replacement Bulbs
*Aquarium UV Bulbs; American Aquarium Level 1 UVC

*
Aquarium Lighting; Information about T5, Metal Halide, CFL, SHO, PUR, PAR, more
This is THE article for in-depth, researched, and regularly updated information on the subject of aquarium lighting; a MUST READ!

Aquarium Filtration, Filters; Help

*
Aquarium Fish Nutrition; Important Ingredients in Fish Feeding

FISH AS PETS
Fish as Pets contains articles and commentary of Interest to the Aquarium Hobby

*
POND CARE INFORMATION

TMC V2 RO Filter systems; the very best you can buy with TDS meter (far superior to 4 stage RO/DI systems sold via Bulk Reef Supply, Amazon, or eBay that use the inferior cellulose triacetate membrane made by Dow):

Reverse Osmosis Aquarium Water Filters; with TDS Meter

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