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AngelFish Disease, Virus
AKA Angelfish Aids, Angel Virus
By Carl Strohmeyer
This can be a very virulent and devastating disease.
All exposed angelfish that are not immune will come down with symptoms within 2-4 days of exposure. Sometimes sooner, as “Angelfish Aids” as it is sometime known as, is highly infectious.
I witnessed many angelfish from fish farms in Southeast Asia that came in as carriers of this virulent infection in the 1990s; as a result many large angelfish breeding operations closed and there was a shortage of angelfish in the retail trade.
During this time, I found some small scale angelfish breeders that were able to avoid exposure to this virus and keep me and others supplied with healthy stock
Clamped fins, excess slime, listless with nose pointed up slightly, usually with the fish on the bottom of the aquarium (unlike Gill Flukes which would have the fish at the surface).
It has an approximately 3 week infectious period. This disease is quite virulent and if an angelfish survives the virus, it may become a carrier for up to six months.
These symptoms can also be caused by other infectious diseases such as Ichthyophonus fungi infections (which are internal), but show similar external symptoms in later stages of the disease.
However one major difference in external symptoms is that the progression of Angelfish Aids/Virus is much quicker than Ichthyophonus, often going from healthy and vibrant to sickly to death in as little as 3-5 days.
Do not also confuse Angelfish Aids/Virus with internal worm infections such as Nematodes or Annelids as these parasitic worm infections often have a bulge in the lower abdomen near the vent, or worms protruding from the anus. As well the progression is again generally not nearly as quick as Angelfish Virus/Aids. Often internal parasite infections can go on for weeks of slowly more noticeable symptoms.
Parasites such as Gill Flukes cause some similar symptoms, although again the progression of Gill Fluke symptoms is much slower than Angelfish Virus as often gill fluke symptoms slowly appear over a week or more time.
Further Reference: Fish Parasites; Worms, Nematodes, Gill Flukes, Treatment, ID
If you suspect that a quarantined fish has this virus, I recommend that you destroy the fish. The risk of spread is too high to keep a potentially infected fish around.
Here is a video of the fish pictured above in a video format; this fish is showing most of the classic symptoms of Angelfish Virus from which I have seen many times (especially during outbreaks during the 1990s).
I also sent the video link to friend in the professional maintenance business that confirmed this.
The other possible diagnosis is Gill Flukes, however as per the owner of this angelfish, the progression of the disease, nor the fish resting on the tank bottom does not indicate a diagnosis of Gill Flukes.
Video Courtesy DaharkazAngel
MODE OF DISEASE TRANSFER
This is where there is not clear evidence (scientific that is), all I have is my observations as well as speaking with other aquarium maintenance professionals experience and brief non-scientific articles about Angelfish Virus.
I will provide a few observations/theories (please note that these are not proven at the time of writing this article):
- Direct transfer in the water column; this seems to be the main mode of transference, which of course quarantine or purchasing of fish from a known good source can help prevent.
As well I have noted that UV Sterilization has helped check the spread of Angelfish Aids to non-immune/exposed fish (which further supports this theory that a Level 1 UV Sterilizer can improve Redox and thus fish immunity, as a UV cannot prevent the spread via feces or similar)
- Transfer via infected water, decorations, or even plants; this is similar to the above and similar preventative measures as above should be taken to prevent this mode of transfer
- Transfer via direct contact/feces; I personally do not support this mode of transfer as I have not observed it nor has the few tests to check the spread bear this out, however a few knowledgeable persons I know (or read) have postulated this.
- Incubation of the virus; as noted in the symptoms section of this article, it has been espoused that a fish can be a carrier for up to six months.
Since immunity is the objective, it is important to keep the angelfish comfortable while giving the immune system time to fight this virus (if it can).
Part of the problem is this virus moves so fast, the fish’ immune system cannot respond quick enough, so optimal conditions is a must.
This includes the little known among aquarists parameter of Redox Balance which may be quite important for immunity during times of viral infection)
Also as per Redox, it is noteworthy that my incidence of Angel Fish Virus deaths was considerably higher in aquariums kept in low pH environments under 6.5. This is likely due to the poor Redox balance in low pH aquariums since acidic environments are oxidizing and allow for little or no Redox Reduction!!
Secondary bacterial and Fungal/Saprolegnia infections are also often issues during Angelfish Aids infections from my experience.
Understanding the Aquarium Redox Potential for Fish Health
- Removal of any bright lights from the aquarium.
A darkened quarantine tank with a seasoned Sponge Filter is strongly recommended).
Product Source: Premium Aquarium Sponge Filters, only from AAP
- A medicated Bath utilizing Methylene Blue is recommended.
Further Information: Fish Bath, Dips, Aquarium Answers
Product Source: Methylene Blue from AAP
- Treatment (again preferable in quarantine for Angelfish Virus), may include a “cocktail” of SeaChem ParaGuard, Nitrofurazone, and Kanamycin
*SeaChem ParaGuard; Anti fungal, viral, virus treatment
*Nitrofurazone (Furan 2)
*SeaChem Kanaplex anti bacterial
- Treat as the medications suggest until symptoms are gone plus 3 days
- Partial water changes between each treatment along with strict monitoring of water parameters; ammonia, nitrites, even GH & KH is a must.
Slowly increasing mineral cations in a low pH aquarium may help by improving Redox balance. The use of mineral blocks such as Wonder Shells in 1/4 does is a simple but effective way to perform this.
Product Source: Wonder Shells, Unique AAP Version not sold elsewhere
- The addition of a Level 1 or 2 capable UV Sterilizer to the main display tank while the fish are in quarantined is strongly urged to aid in stopping the water borne spread of the virus and improve Redox Balance.
This is a MUST to check the spread of this disease! Even if all your angels died, it is essential to prevent new angles or other fish that might be added later to contract this insidious infection.
I also suggest not replacing your angels for at least two weeks.
Also once added, maintenance of the UV Sterilizer is a must by changing the UV Bulb once every six months with a low pressure level 1 capable UVC bulb!
*True Level 1 Aquarium or Pond UV Sterilizers
*Level 1 Capable Low Pressure UV Bulbs; American Aquarium
Although I have given a method of treatment, please do not let me give the reader too much false hope; as even with strictly following this treatment regimen, chances of success are less than 50% from my experience (many aquarists choose to put the fish down rather than to treat and this is a valid option in my humble opinion as well).
However I have also had success with this treatment regimen (much more so than doing nothing), so if you are willing or able to strictly follow it, you may have success.
Either way, with success, failure, or putting the fish down; prevention of spread to other angelfish (or some other fish as well) should be considered.
Multiple water changes, optimum water parameters, UV Sterilization, and holding off from adding other angelfish for 3-6 months should all be considered.
*Aquarium Cleaning, Water Change Methods, more
*Aquarium Chemistry; For Optimum Water Parameters
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