Neobenedenia

[Carl Cardarelli]

Can anyone advise me of a medication I can use to get rid of the parasite, I have tried CP, praziquantel and copper several times for the last year to no avail. Can't place fish in quarantine due having 24 and some are 12 inches and bigger. Tank is 600 gallons 12 ft long fish only.

I appreciate any advice on how to beat Neobenedenia, Thanks

 

[supernanoguy]

Have you tried metroplex/kana and focus?

 

[ThRoewer]

Assuming by the list of medications you already tried that this is a fish only system I would suggest to try hyposalinity.
It would still be best not to do this in the display but rather place the fish in something like a kiddie pool or something equaly sized.
There are also such aggressive medications as dylox but I would rather try avoiding those.

 

[Carl Cardarelli]

Have you tried metroplex/kana and focus?

yes to no avail

 

[Carl Cardarelli]

Assuming by the list of medications you already tried that this is a fish only system I would suggest to try hyposalinity.
It would still be best not to do this in the display but rather place the fish in something like a kiddie pool or something equaly sized.
There are also such aggressive medications as dylox but I would rather try avoiding those.

what would the procedure look like Thanks

 

[Jay Hemdal]

Carl,

Below is an excerpt from my upcoming fish disease book. Jump to the last paragraph to find my take on using hypo for Neo. It has worked for me every time.

Neobenedenia melleni (eye flukes)

These are relatively large (up to 8 mm), egg-laying worms that live on the skin or eyes of marine fishes.



Symptoms

Neobenedenia infections peak slowly; there may be no symptoms for weeks after you acquire a fish. Eventually, as the flukes multiply and grow in size, they begin to cause symptoms of disease.



The first obvious symptom may be slightly cloudy eyes, caused by the transparent fluke feeding on the eye tissue and eliciting a tissue reaction. This gives this worm the common name of “eye fluke,” although it is unknown whether these worms actually prefer to feed on eye tissue, or whether that is just where they first become apparent.



As the infection becomes more serious, the fish will “flash,” their skin color will become dull, their fins may become tattered, and they just generally get a “scruffy” look to them. Rapid breathing due to stress, possible secondary infection, and then death follow if treatment is not begun.



Diagnosis

The best means of diagnosis is to give the fish a five-minute freshwater dip. Not only does this knock back the infection by killing the adult parasites, but even a casual look at the bottom of the dip container afterwards will help to positively identify this disease. The worms turn whitish and fall to the bottom. Many aquarists mistake these for scales that were dislodged from the fish. However, looking at these “scales” under a dissecting microscope, or even a hand lens, will soon show them for what they are—dead worms.



Sometimes a fish’s history can help diagnosis at least the potential for this disease. Angelfishes and butterflyfishes are especially prone to Neobenedenia infections, so any of these fish that have been housed at an import facility that doesn’t prophylactically treat for trematodes stand a very good chance of being infected.



Angelfish, Pomacanthus sp. ++

Barrimundi, Lates sp. ++

Batfish, Platax sp. +++

Butterflyfish, Chaetodon sp. ++

Cichlid, Tilapia sp. +++ (when housed in seawater)

Invertebrates 0 (but may carry eggs)

Jacks, Caraganidae +++

Lionfish, Pterois sp. +

Lookdowns, Selene sp. +++

Pyramid butterflyfish, Hemitaurichthys sp. +++

Grouper family, Serranidae ++

Garden eel, Taenioconger sp. +

Remora, Echeneis sp. +

Sharks and rays, Elasmobranchs 0

Surgeonfish, Acanthurus sp. ++

Spadefish, Chaetodipterus faber +++



Aquarium hosts for Neobenedenia sp. 0=not infected, + = sometimes infected, ++=commonly infected, +++=very commonly infected (From Bullard et-al 2000 and personal obs.)



Treatment

Many people suggest using a freshwater dip as a treatment for all incoming fish. The two drawbacks to this are 1) the dips are not 100% effective (and do not harm the fluke eggs) and 2) newly acquired fish often do not stand up well to the added stress of a freshwater dip when they first arrive.



Neobenedenia eggs can take 14 to 30 days (or longer?) to hatch as motile larvae called oncomiracidium. Additionally, the eggs have sticky tendrils that attach them securely to all manner of objects in an aquarium. There is some merit to the idea of keeping a treatment tank free of substrate and siphoning the bottom regularly in order to remove some of these unhatched eggs. There have been reports that Lysmata cleaner shrimp feed on these eggs, rendering them non-viable. However, it is unlikely that in a normal aquarium, with many other food choices, that cleaner shrimp will markedly reduce their numbers.

Any successful treatment for these worms must be undertaken in stages. The first treatment kills off the adult worms (but this won’t kill the eggs), and the subsequent treatments kill off the juvenile worms after they have all hatched but before any of them have matured and begun to lay eggs of their own. Due to variables in timing, it is virtually impossible to accomplish this in only two treatments.



Whole-tank formalin baths at 166 ppm for one hour will eliminate the adult flukes from an aquarium but not the eggs. Because this type of treatment has no residual effect, the treatment may need to be repeated every two weeks for two or three more times. Experience in public aquarium exhibits has shown that this method rarely clears a tank completely of this pest.



A better alternative is a Praziquantel treatment at 4 ppm, followed by a 50% water change after 48 hours, then a second treatment 12 to 14 days later, followed by another 50% water change 48 hours later.



At the Toledo Zoo Aquarium, we noticed that multiple Praziquantel treatments on the same system, over months to years, required higher and higher doses, combined with increased frequency of the treatments in order to maintain effectiveness. Eventually, the praziquantel was simply no longer effective. One supposition was that the target parasites were building an immunity to the drug. That seemed unlikely as genetic change in multi-cellular organisms typically takes longer to happen (as opposed to drug-resistant bacteria that can develop resistance in short order). We wondered then, what could be rendering Praziquantel so ineffective on repeat doses?

Subsequent research indicates that bacterial degradation of the Praziquantel (Thomas et-al, 2016) is the process at work. Their study concluded that while Praziquantel is stable for over two weeks in sterile marine aquarium water, when dosed in working systems, it degrades below detectable limits in just nine days. A subsequent dose on the same system showed a reduction in Praziquantel in less than 48 hours. The presence or absence of fish in the system did not affect this rate of degradation. The natural bacterial population of the aquarium actually works to eliminate Praziquantel from the water.



Barrett L. Christie, a public aquarium curator, has researched a variety of treatment methods and has struck upon one that is highly effective. The treatment is relatively simple; in a quarantine system, the fish are exposed to hyposalinity (low salinity) for 35 days. Exactly how low of a salinity is the variable that needs to be controlled. Some species of fish do not tolerate lower salinities, yet if the salinity is not reduced enough, the parasite population is only reduced, not eradicated. Barrett has hit upon a workable value of 17 parts per thousand, a bit less than half the salinity of normal seawater (this equates to a specific gravity of around 1.013). Obviously, most invertebrates cannot be present during this sort of treatment. Sharks and some rays cannot tolerate it either. Assuming the fish are healthy in all other respects, you begin this treatment by lowering the salinity to the target value over 24 to 48 hours. During the low salinity treatment, water quality must be monitored closely, especially pH. Be aware that some other diseases, notably Uronema and Amyloodinium thrive at lower salinities. Luckily, another common scourge, marine ich, Cryptocaryon irritans, is also inhibited by low salinity. After 35 days, the salinity is gradually raised back to normal. It is imperative to perform this change back to normal seawater very slowly. While marine fish tolerate a drop in salinity very well, their kidneys have more difficulty adjusting as the salinity is raised. Never return fish to normal salinity faster than 72 hours, and don’t make large changes at one time.



Jay

 

[ThRoewer]

Have you tried metroplex/kana and focus?

yes to no avail

Those medications have little to no effect on Neobenedenia or other Monogeneans.

Effective treatments are:

- Praziquantel
The problem with Praziquantel is that in an established tank bacteria may break it down too fast to be effective.
Best used in a sterile quarantine/treatment tank.

- Hyposalinity
Hyposalinity should be highly effective against Capsalidae but some Monogeneans are euryhaline enough to survive it. Only suitable for fish-only tanks. Also, bringing a fully stocked and established display tank down in salinity can result in massive die-offs of other micro organisms, algae, crustaceans, and what else is there other than fish, and cause deadly ammonia spikes.
Again, best used in a quarantine/treatment tank. Alternatively the salinity can be brought down slowly (1 ppt per day) while closely monitoring ammonia.

Effects of temperature and salinity on the life cycle of Neobenedenia sp. (Monogenea: Capsalidae) infecting farmed barramundi (Lates calcarifer)

- Trichlorfon/Metrifonate (Dylox, Masoten,...)
Effective but I would rather not use it and not recommend it. People at public aquaria, who should know what they are doing, managed to kill lots of fish with it due to overdosing.
Aside from being potentially harmful to fish it will also kill all crustacean (from tiny copepods to shrimps and crabs) in your tank and by that may set off an ammonia spike.

- Formalin
Whole tank treatments are problematic to say the least. Prolonged exposure may also harm the fish.
Best used as short term bath in a quarantine/treatment tank.

Reproductive Strategies of the Insidious Fish Ectoparasite, Neobenedenia sp. (Capsalidae: Monogenea)

Something to look into:
Plant extracts as a natural treatment against the fish ectoparasite Neobenedenia sp. (Monogenea: Capsalidae)
Also here: https://www.cambridge.org/core/jour.../F54674248E0D35465F8D3D6AB72D0A62/core-reader

Ultimately I would suggest you find a way to set up a suitable treatment tank (kiddie pool or something like that) to do an effective treatment of the fish without nuking your tank.

 

[Carl Cardarelli]

Carl,

Below is an excerpt from my upcoming fish disease book. Jump to the last paragraph to find my take on using hypo for Neo. It has worked for me every time.

Neobenedenia melleni (eye flukes)

These are relatively large (up to 8 mm), egg-laying worms that live on the skin or eyes of marine fishes.



Symptoms

Neobenedenia infections peak slowly; there may be no symptoms for weeks after you acquire a fish. Eventually, as the flukes multiply and grow in size, they begin to cause symptoms of disease.



The first obvious symptom may be slightly cloudy eyes, caused by the transparent fluke feeding on the eye tissue and eliciting a tissue reaction. This gives this worm the common name of “eye fluke,” although it is unknown whether these worms actually prefer to feed on eye tissue, or whether that is just where they first become apparent.



As the infection becomes more serious, the fish will “flash,” their skin color will become dull, their fins may become tattered, and they just generally get a “scruffy” look to them. Rapid breathing due to stress, possible secondary infection, and then death follow if treatment is not begun.



Diagnosis

The best means of diagnosis is to give the fish a five-minute freshwater dip. Not only does this knock back the infection by killing the adult parasites, but even a casual look at the bottom of the dip container afterwards will help to positively identify this disease. The worms turn whitish and fall to the bottom. Many aquarists mistake these for scales that were dislodged from the fish. However, looking at these “scales” under a dissecting microscope, or even a hand lens, will soon show them for what they are—dead worms.



Sometimes a fish’s history can help diagnosis at least the potential for this disease. Angelfishes and butterflyfishes are especially prone to Neobenedenia infections, so any of these fish that have been housed at an import facility that doesn’t prophylactically treat for trematodes stand a very good chance of being infected.



Angelfish, Pomacanthus sp. ++

Barrimundi, Lates sp. ++

Batfish, Platax sp. +++

Butterflyfish, Chaetodon sp. ++

Cichlid, Tilapia sp. +++ (when housed in seawater)

Invertebrates 0 (but may carry eggs)

Jacks, Caraganidae +++

Lionfish, Pterois sp. +

Lookdowns, Selene sp. +++

Pyramid butterflyfish, Hemitaurichthys sp. +++

Grouper family, Serranidae ++

Garden eel, Taenioconger sp. +

Remora, Echeneis sp. +

Sharks and rays, Elasmobranchs 0

Surgeonfish, Acanthurus sp. ++

Spadefish, Chaetodipterus faber +++



Aquarium hosts for Neobenedenia sp. 0=not infected, + = sometimes infected, ++=commonly infected, +++=very commonly infected (From Bullard et-al 2000 and personal obs.)



Treatment

Many people suggest using a freshwater dip as a treatment for all incoming fish. The two drawbacks to this are 1) the dips are not 100% effective (and do not harm the fluke eggs) and 2) newly acquired fish often do not stand up well to the added stress of a freshwater dip when they first arrive.



Neobenedenia eggs can take 14 to 30 days (or longer?) to hatch as motile larvae called oncomiracidium. Additionally, the eggs have sticky tendrils that attach them securely to all manner of objects in an aquarium. There is some merit to the idea of keeping a treatment tank free of substrate and siphoning the bottom regularly in order to remove some of these unhatched eggs. There have been reports that Lysmata cleaner shrimp feed on these eggs, rendering them non-viable. However, it is unlikely that in a normal aquarium, with many other food choices, that cleaner shrimp will markedly reduce their numbers.

Any successful treatment for these worms must be undertaken in stages. The first treatment kills off the adult worms (but this won’t kill the eggs), and the subsequent treatments kill off the juvenile worms after they have all hatched but before any of them have matured and begun to lay eggs of their own. Due to variables in timing, it is virtually impossible to accomplish this in only two treatments.



Whole-tank formalin baths at 166 ppm for one hour will eliminate the adult flukes from an aquarium but not the eggs. Because this type of treatment has no residual effect, the treatment may need to be repeated every two weeks for two or three more times. Experience in public aquarium exhibits has shown that this method rarely clears a tank completely of this pest.



A better alternative is a Praziquantel treatment at 4 ppm, followed by a 50% water change after 48 hours, then a second treatment 12 to 14 days later, followed by another 50% water change 48 hours later.



At the Toledo Zoo Aquarium, we noticed that multiple Praziquantel treatments on the same system, over months to years, required higher and higher doses, combined with increased frequency of the treatments in order to maintain effectiveness. Eventually, the praziquantel was simply no longer effective. One supposition was that the target parasites were building an immunity to the drug. That seemed unlikely as genetic change in multi-cellular organisms typically takes longer to happen (as opposed to drug-resistant bacteria that can develop resistance in short order). We wondered then, what could be rendering Praziquantel so ineffective on repeat doses?

Subsequent research indicates that bacterial degradation of the Praziquantel (Thomas et-al, 2016) is the process at work. Their study concluded that while Praziquantel is stable for over two weeks in sterile marine aquarium water, when dosed in working systems, it degrades below detectable limits in just nine days. A subsequent dose on the same system showed a reduction in Praziquantel in less than 48 hours. The presence or absence of fish in the system did not affect this rate of degradation. The natural bacterial population of the aquarium actually works to eliminate Praziquantel from the water.



Barrett L. Christie, a public aquarium curator, has researched a variety of treatment methods and has struck upon one that is highly effective. The treatment is relatively simple; in a quarantine system, the fish are exposed to hyposalinity (low salinity) for 35 days. Exactly how low of a salinity is the variable that needs to be controlled. Some species of fish do not tolerate lower salinities, yet if the salinity is not reduced enough, the parasite population is only reduced, not eradicated. Barrett has hit upon a workable value of 17 parts per thousand, a bit less than half the salinity of normal seawater (this equates to a specific gravity of around 1.013). Obviously, most invertebrates cannot be present during this sort of treatment. Sharks and some rays cannot tolerate it either. Assuming the fish are healthy in all other respects, you begin this treatment by lowering the salinity to the target value over 24 to 48 hours. During the low salinity treatment, water quality must be monitored closely, especially pH. Be aware that some other diseases, notably Uronema and Amyloodinium thrive at lower salinities. Luckily, another common scourge, marine ich, Cryptocaryon irritans, is also inhibited by low salinity. After 35 days, the salinity is gradually raised back to normal. It is imperative to perform this change back to normal seawater very slowly. While marine fish tolerate a drop in salinity very well, their kidneys have more difficulty adjusting as the salinity is raised. Never return fish to normal salinity faster than 72 hours, and don’t make large changes at one time.



Jay

Thank you so much I have one question I have 2 zebra eels and some hermit crabs will they be ok in the low salinity again thank you Carl

 

[Carl Cardarelli]

Thank you so much I have one question I have 2 zebra eels and some hermit crabs will they be ok in the low salinity again thank you Carl

bye the way let me know when the book is out like to purchase it

 

[Jay Hemdal]

Thank you so much I have one question I have 2 zebra eels and some hermit crabs will they be ok in the low salinity again thank you Carl

The zebra eels may go off their feed, and the hermit crabs may not survive (depends on the species).

Jay

 

[Carl Cardarelli]

The zebra eels may go off their feed, and the hermit crabs may not survive (depends on the species).

Jay

I want to thank you for helping me with my issue with the tank. I have talked to so many people and no one could help me. This has been going on for 2 years. Can you tell me over what period of time should I drop the salinity. My tankis 600 gallons. Again thank you for your time.

 

[Jay Hemdal]

I want to thank you for helping me with my issue with the tank. I have talked to so many people and no one could help me. This has been going on for 2 years. Can you tell me over what period of time should I drop the salinity. My tankis 600 gallons. Again thank you for your time.

You can drop the specific gravity over 48 hours with no problem. Be sure to monitor the pH of the tank during this, you may need to buffer it at times. I would do a big water change going into it, as performing water changes during hypo is a bit of a trick. If your tank has a bare bottom, or thin sand layer, siphoning that will help reduce the number of Neobenedenia eggs. At the end of 35 days, you need to bring the specific gravity back up very slowly - I would take five full days. In giving it some more thought, if the fish are handling the hypo well, go 40 days...I would hate for it to come back after all this.

One other thing - there are other capsalid trematodes in addition to Neobenedenia. The thought is that some species are from brackish water. I've not come across these myself, but be aware that they could be out there, and hype won't work for them. Did you ever have lookdowns, spadefish or other inshore/bay fish in this tank?

Jay

 

[ThRoewer]

I want to thank you for helping me with my issue with the tank. I have talked to so many people and no one could help me. This has been going on for 2 years. Can you tell me over what period of time should I drop the salinity. My tankis 600 gallons. Again thank you for your time.

In a quarantine tank you can go down to the therapeutic salinity within hours or, like I usually do it, drop the fish straight in after temperature acclimatization and pH alignment.

In a display where you always - even in a fish only system - have algae, bacteria, micro organisms, and other small inverts (pods, worms,...) you must go slower to avoid a sudden die-off of that micro fauna and resulting ammonia spike. I did not follow this approach once and killed all my fish in that tank that way...

 

[Carl Cardarelli]

You can drop the specific gravity over 48 hours with no problem. Be sure to monitor the pH of the tank during this, you may need to buffer it at times. I would do a big water change going into it, as performing water changes during hypo is a bit of a trick. If your tank has a bare bottom, or thin sand layer, siphoning that will help reduce the number of Neobenedenia eggs. At the end of 35 days, you need to bring the specific gravity back up very slowly - I would take five full days. In giving it some more thought, if the fish are handling the hypo well, go 40 days...I would hate for it to come back after all this.

One other thing - there are other capsalid trematodes in addition to Neobenedenia. The thought is that some species are from brackish water. I've not come across these myself, but be aware that they could be out there, and hype won't work for them. Did you ever have lookdowns, spadefish or other inshore/bay fish in this tank?

Jay

Thanks as far as fish no lookdowns or spadefish ever have a large bat fish, 6 puffers, 4 tangs, 2 angels, 6 clowns, 3 eels, 3 wrasses one large broom tail. When I first started hobby again 2 years ago I purchased some fish from a shop in Ft Lauderdale that had every parasite known to mankind, so since the beginning of this hobby I been fighting ick, Fluke and now this and I mean no stop in over 2 years. I was going to take about 5-7 days to lower the salt.

 

[Jay Hemdal]

I’ve had orbic batfish get really resistant capsalid trematodes, nothing worked. That said, that was years before I learned about the hypo treatment....
Jay

 

[Privateye]

I'm curious, is there any information out there about biological controls or cleaner organsisms? I know Spiringer's damsels eat flatworms, but I'm not sure if they'd eat these. Even so, I'm not sure how well they would fare with eels.

 

[Jay Hemdal]

I'm curious, is there any information out there about biological controls or cleaner organsisms? I know Spiringer's damsels eat flatworms, but I'm not sure if they'd eat these. Even so, I'm not sure how well they would fare with eels.

For decades, I’ve maintained that cleaner animals won’t control acute infections in aquariums, and while that is true, some recent research has proven that cleaner shrimp eat Neobenedenia eggs at night! This won’t cure the fish, but it does make treatments easier. Thanks for reminding me about that!
Jay

 

[Privateye]

For decades, I’ve maintained that cleaner animals won’t control acute infections in aquariums, and while that is true, some recent research has proven that cleaner shrimp eat Neobenedenia eggs at night! This won’t cure the fish, but it does make treatments easier. Thanks for reminding me about that!
Jay

Hmm I wonder about their abilities to prevent infections, even if they can't control them. It's speculation at best though. When it comes to coral flatworms, Springers damsels have quite a reputation!

 

[Carl Cardarelli]

I’ve had orbic batfish get really resistant capsalid trematodes, nothing worked. That said, that was years before I learned about the hypo treatment....
Jay

started lower salt today thanks again Carl

 

[Carl Cardarelli]

started lower salt today thanks again Carl

Have somewhat of a dumb question I have a friend that told me he wouldn't lower the salinity, If I don't it only a matter of time when they all have it and eventually die from it because in time it will get out of control . You agree? Sorry to bother you and thanks again