Aquarium Shrimp Diseases and Pest

1. Vorticella

Vorticella parasite looks like White fungus or mould growth on the shell of the shrimp, normally on the tip of the shrimp nose.

Vorticella is actually a protozoa of 16 known species, not a fungus at all. Vorticella are aquatic organisms, most commonly found in freshwater habitats. They attach themselves to plant detritus, rocks, algae, or animals (particularly crustaceans).

Vorticella are heterotrophic organisms. They prey on bacteria. Vorticella use their cilia to create a current of water (vortex) to direct food towards its mouth.

Typically, Vorticella reproduce via binary fission. The new organism splits from the parent and swims until it can find something on which to anchor itself.

If left untreated, vorticella have been known to cause the death of the shrimp it was attached to.

Here are examples of what it looks like.


Known cures:

Salt bath with aquarium salts. Be careful not to use table salt with Iodine.
Dosage:   1 teaspoon to 1 cup of clean tank water (not tap water).
Duration: 30sec to 1 minute. You might need to repeat this a couple of times until the vorticella disappears, so keep the infected shrimp in a breeder or hospital tank (could be another cup of tank water).
Possible causes: Poor water conditions. Increase water change frequency.

Low doses of the salt bath have been know to be ineffective.
Ick and fungus cure medicines don’t work on Vorticella.
Seachem Paraguard could work as well at the full recommended dosage, since this is a parasitic med. But Seachem have admitted Paraguard isn’t invertebrate-safe. So only try paraguard as a last resort and drip it into the tank premixed from a bucket of tank water slowly .

This treatment is in no way a replacement for good tank husbandry.

So keep up with your water change routines, and removal debris and uneaten food.

2. Bacterial infection:

This is one of those diseases that is still very difficult to diagnose in shrimp. There isn’t much information around.
Nor are there lots of pictures. Bacteria never stop and smile for the camera.

In various “transparent” shrimp species in which the organs are visible from the outside, you can observe an internal infection, the inner translucent bodies which appear dark in healthy shrimp are pink and look as if they were inflamed in infected shrimp. Various studies of diseased shrimp showed that their bodies were infested with micrococci (bacteria). Infected animals with recognizable symptoms die 2-4 days later. Treatment is not yet possible.


Shrimp on left is infected with Micrococci (above)

Very sick Tiger in the picture above.

Symptoms: Unexplained death of multiple shrimp, pinkish flesh, loss of legs or antennae, holes in the shrimp’s carapace, extreme loss of colour

Treatment 1: large water changes (80%) daily.

Treatment 2: Hydrogen Peroxide H2O2 (3%)
Dosage: 1ml / 4L (up to 2ml / 4L if you think the situation is drastic)
Duration: once per day for 5 days.

Treatment 3: UV light (only effective if the bacteria is water borne)
Duration: 5 days.

(Additional suggestion from us:

Treatment 4: GlasGarten Shrimp Fit or Genchem Beta G both treat and prevent the milky white/ cloudiness of the shrimps.)

The infection could be parasitic in nature. And the bacterial infection may be just secondary. So be very careful to examine the shrimp for signs of external parasites first.

Be aware that when you notice visual signs of the symptoms as indicated above, it’s usually very advanced in its infection. Expect more deaths of some shrimp that are too far gone. You might save the rest however. You’ll probably have already lost quite a few shrimp. It’s either do nothing or break the tank down, sterilise it and start again. Or Go for broke and try a treatment.

Hydrogen Peroxide will have the added benefit of killing off any algae in the tank if you don’t like the stuff.

The increase heat in summer weather can also increase the likely hood of bad bacterial growth. To tackle this issue, you can open all the tank lids to let the heat out, also keeping up with topping up water to replace the evaporated one. 

This treatment is in no way a replacement for good tank husbandry. So keep up with your water change routines, and remove debris and uneaten food. 

3. Parasites/ Bugs: 

These might not necessarily be detrimental to the shrimp.
Many live in a symbiotic relationship with the shrimp as can be seen in wild shrimp.
But if it was me, I say burn them parasites!



Leeches :


Treatment is the same as Vorticella.

Known cures: Salt bath with aquarium salts. Be careful not to use table salt with Iodine.
Dosage: 1 teaspoon to 1 cup of clean tank water (not tap water).
Duration: 30sec to 1 minute. You might need to repeat this a couple of times until the parasite drops off, so keep the infected shrimp in a breeder or hospital tank (could be another cup of tank water) to allow easier re-treatment.

Another treatment that has been known to work is Genchem “No Planaria”.
Suggestion from us: Use half the Dosage as per instructions on the packaging of No Planaria.
Duration: 3 days, although you might see the pests disappear after one day, continuing treatment will ensure any unseen parasites are also killed.
Perform a water change at the end of No Planarian treatment.
Watch for ammonia spike and treat if necessary.

 Another product that might be useful in treating these pests is a product called “Internal Parasite Clear” by Guangzhou Bigfish Aquarium Corp.

4. Dragonfly Nymphs:

While these are not specifically a disease, having one or more of these nasty bugs in your tanks is sure death for shrimp (even small fish). As the nymphs will eat any baby shrimps or weak adult shrimps.

Check out the pics below and you’ll understand why. Use these to help you identify them too.


The only treatment is removal manually.
Locate the nymph and use a net to manually remove them.

5.  Muscular Necrosis:

Shrimp with this condition is diagnosed with a white or milky discolouration of its back part, more specifically, the muscle tissue within its shell. This symptom is called Muscular Necrosis. Necrosis in biological terms is understood to be the destruction of one or more cells in a living organism. The result is an inflammatory reaction or decomposition of the surrounding tissue. Proteins produced by the decomposition of the cells will be released. And the milky white colour is seen in the tail part.

Muscular Necrosis in a White Pearl shrimp


Symptoms of muscular necrosis can be caused by

  •        Incorrect water parameters
  •        Bacterial infection
  •        Myxosporidien

Stresses in big pH changes, lack of nutrients and oxygen deprivation, can also lead to cell death under certain circumstances. This milky white discolouration usually begins in the tail region and spreads in a few days towards the head until the whole rump is a milky white appearance.

Treatment: Isolate the infected shrimp immediately, as muscular necrosis can be infectious. Generous daily water changes can often abate the disease. However, if the condition has affected the entire abdomen, a cure is no longer possible and the shrimp will die within a few days.

Check water parameters in the main tank. Ensure all parameters are within tolerated ranges for the species. This includes temperature, pHKHGH,TDS, Ammonia, Nitrite, Nitrates, and oxygen levels.

6. Fungal Infections:

Fungal infections are common in the fish hobby, but it possible for shrimp to get fungal infections as well.
It’s unavoidable, since fungal spores are everywhere, in the air and water.
Fungi are plant like organisms but unlike plants are not capable of photosynthesis. All fungal diseases are called Mycosis (plural: mycoses). Internal infestation by fungal spores is usually ingested by food. If the immune system is intact, the shrimp can fight it off. However, if the internal organs are infected by fungal spores, death is possible. Internal diagnosis is difficult and only possible under a microscope.
An external/superficial mycosis infection however is visible to the naked eye. Symptoms of superficial fungal infection caused by Achlya or Saprolegnia can be seen as white fluffy cotton growths in the abdomen or head areas. As mentioned fungi are usually fought off by a healthy immune system, so we only see this in weakened or injured shrimp or just after a moult. The moulting process takes a lot of energy out of the shrimp and it’s immune system will be heavily loaded. It’s during these moments when the shrimp have been weakened that fungi can take hold. Spores attach themselves to weakened sites on the shrimp and break out as a cottony white growth.

If not treated quickly, the spores will invade any dead tissue cells and in the process infect more tissue causing a greater infection.

At times, if the infection is only on the surface of the shrimp’s shell, a moult can get rid of the fungus. It is only by timeliness/chance that such a situation could rectify itself. At other times, treatment is required.


Treatment: Separate the infected shrimp and treat with JBL’s Fungol

Dosage: follow packaging instructions for the dosage and duration.
Note: JBL Fungol does not contain copper but it also says not to use it with invertebrates.
If left untreated the shrimp will die, so a certain risk in using the product is going to be required.
Fungol could be replaced with a similar fungal medication, but check that the product does not contain copper at least.

7. Chitinolytic bacterial disease, Shell disease, Brown spot disease, Black spot disease, Burned spot disease, Rust disease:

While the Bacterial Infection post above is an example of internal infections, this one is more an external infection (unless erosion of the shell is severe).

This is essentially a bacterial infection of Chitinolytic bacteria (Gram negative rods) including Vibrio spp. , Benekea spp., Pseudomonas spp., Aeromonas spp., Spirillum, spp. and Flavobacterium spp.

The impact on the shrimp is visible as the exoskeleton becomes pitted, eroded, and melanized at the site of infection.

Diagnosis: Erosion of chitin demarked by dark brown to black pigmentation demonstrates chitinolysis. Marks change colour from a rusty to a brown and finally a black colour. Ulcers form on these lesions, as the bacteria will destroyed muscle tissues under the shell. This opens the shrimp up to other secondary infections. The most common sites of infection is the gill, abdominal muscle belly, tail section and gastropods. Seriously infected will just lie on its side, only gastropods and gills in motion.

Pictures of infected CRS seem to exhibit infection on the red areas and not on the white areas of the shrimp.

Advanced infection of CRS


Early infection of CRS


Pic coutesy of Pedro – Taiwan bee with signs of Chitinolytic bacteria


Possible causes:
There are many possible causes. Tank hygiene and maintaining water quality are crucial.

  •        Poor water conditions
  •        Unhealthy or injured shrimps
  •        Too much Nitrates
  •        chemical imbalance
  •        substrate turned bad (Usually happens after long usage of substrate)


Treatment 1:

Levamisole HCL from a product called Big L’s pig and poultry wormer cleared shrimp of this disease.

Dose is 1ml per 7 litres of aquarium water. Re-dose after 48 hours if needed.

However, there are a few other things you can also try…


Strict quarantine – every tank showing any signs, at all. And those tanks that have been exposed to contamination – nets, plants, hands… anything that has shared the same water must be assumed to be contaminated. Quarantine also means, do NOT buy or sell any shrimp.

Isolate the infected shrimps to separate hospital tank.

Disinfect all tools – nets, tweezers, etc. Boiling them is enough.

Water change – Water change is essential, at most 1/3 of the water as the shrimps are very sensitive to water changes! However, more might be necessary if the situation is bad.

Remove all items in the tank – disinfect them if suitable. Boil it if practical, otherwise letting them dry out in the sun is usually sufficient. Removing items out of the tank will also help you spot any other dead or infected shrimp that will need to be separated/removed.

Increase oxygen and flow rate.

Add Beneficial Bacteria supplements, for e.g Benibachi Bee Max, Lowkeys Speed Sand, Borneowild Enlive

Other possible Treatments to try:
1) Raise pH slightly & slowly by 1 point – the bacteria might prefer acidic conditions. (Assumes your pH is low for CRS. Try the opposite for Cherry shrimp).

2) Add Aquarium Salt to the separated shrimp – High salinity kills most freshwater bacteria by osmosis – they dehydrate. Note: this is a 1-2 minute salt bath only, do not keep the shrimp in salty water too long.

3) Slowly lower temps – bacteria love higher temps, and your shrimp love lower temps. Bacteria usually have an optimum temperature level where they thrive.

4) Since Cyanobacteria is a … bacteria … treatment could be similar. So do what you have to for the shrimp as if you are treating for Cyanobacteria.

5) Add aquatic plants to consume excess nutrients and nitrates.

6) Of course maintaining the quality of water within the optimum range is key to prevention, removing the dead and infected shrimps, reducing the stocking intensity, providing good nutritious feed.

7) Check the “Bacterial Infection” post above for treatment tips as well.

8) Finally, drastic measures – incorporating terramycine at the rate of 0.45 mg per kg of feed for two weeks. And bath treatment using 0.05 to 1.0 mg of malachite green per litre of water are some of the remedial measures suggested to counteract the incidence of bacterial diseases in prawns.

If caught early enough before the bacteria has eroded through the shell, it is possible to reverse this condition. There have been several cases of the black spots disappearing by itself with a change in water quality.

8. Anti-bacterial treatments

Here are some natural remedies for suspected bacterial infections.
These treatments have been known to work for some people, and are safe for use in your shrimp tank.

Antibacterial – Crack Willow bark or Indian Almond Leaves/ Guava Leaves
The bark of the Crack Willow tree was used as an antibacterial treatment. It’s not so absurd, as tree bark is known to have antibacterial properties. Either Fresh or Dried bark. 2-3 strips of bark 5cm x 2cm.
Change pieces of bark after 2 weeks. And discontinue treatment after 4 weeks.

However, shrimp that might already be infected will still die.

Barks of other trees could also be used, but ensure that it is as clean as possible, there is no sap, and isn’t showing signs of rot (as that indicates the tree is weakened and lacking antibacterial properties itself).

Can be supplemented with an treatment that is eaten below to treat internally.

Antibacterial – Fennel greens
The green fresh leaves of the fennel bulb can be fed dried or blanched. Works as an antibacterial treatment internally. As with all fresh food sources, remember to wash well, and ensure it’s free of pesticides.

Antifungal – Black or Green Tea
(Important: Do NOT use flavoured tea blends. Tea from organic or health food stores preferred)

Tea contains antibacterial and fungicidal tannins.

Green tea is especially preferred, as varieties like Bancha or Kukicha are low in caffeine and green tea on average contains more polyphenols than Chinese teas.

Pour tea as usual, and either drink or discard the first infusion. Only use the 2nd or 3rd infusion.
1ml of tea to 1L of aquarium water. 25% water change after 2 days. Add more tea to the water change adjusting the tea amount to the water changed. So if you change 1L of water add another 1ml of tea.

Alternatively you can use a green tea bag. Infuse tea bag for half a minute, and either drink or discard the first infusion. Then hang the tea bag in the tank. Note: if the tea bag is made of paper, it might either dissolve or get eaten by shrimp. So check often to ensure the contents aren’t going to spill into your tank.

Anti bacterial/Fungicidal – dried almond/ guava/ oak/ banana leaves
Like Indian Almond leaves, these leaves offer the same antibacterial and fungicidal treatments by releasing tannins, essential oils and humic acids.

3 leaves to 100L of water.
Leaves can remain till it’s eaten of dissolved.
Harvest leaves that are dried naturally during the change in seasons.

Antibacterial + Antifungal – Cinnamon sticks
Releases essential oils and tannins.
Dose 1 cinnamon stick bought from health food stores (not cinnamon sticks for decorations) of about 5-7cm per 20L of water volume. The sticks can remain in the tank after treatment. Or remove it if it does not match your decoration tastes.

Antibacterial + Antiparasitic – Salt bath
Already discussed earlier in this sticky.
Salt bath with aquarium salts. Be careful not to use table salt with Iodine. Pure Sea water rock salts are also ok.
Dosage: 1 teaspoon to 1 cup (250ml) of clean tank water (not tap water) prepared as an external bath (do not pour directly into your tank).
Duration: 30sec to 1 minute. You might need to repeat this a couple of times

Try not to dose your main tank directly, but instead, remove the problematic shrimp and treat outside the main tank.

Preventative fungal or bacterial infections and assisting in moulting
Dried Indian Almond Leaves, Guava Leaves and to a lesser extent Oak/ Beech leaves contain humic substances that are slightly antibacterial and anti-fungal. Only dried and brown leaves of deciduous trees should be used.
No ornamental trees or house plants should be used. An added benefit these leaves serve is that they are another food source the shrimp can eat.

Alder cones contain fulvic acids (humic substances), buffer the pH at about 6 to 6.5, have a slightly anti-bacterial and fungicidal properties.

Shrimp Corner also recommend using Saltyshrimp Black Water Fulvin SE+ which has been tried & tested and certificate to be use.

For those of you who might be lucky enough to be able to source alder cones in Australia, and you don’t mind the tannins produced, you have a good source of natural fulvic acids. As an added benefit, alder cones can be eaten by shrimp too.

Antibacterial + Antifungal – The guava leaf.
The guava tree carries with it a little known fact. It has active ingredients in its leaves which fights against bacteria such as E. coli, Salmonella, Pseudomonas, Clostridium, and more.

In the freshwater shrimp tank, guava leaves have been proven to prevent and eliminate the notorious gram-negative bacilli, facultative anaerobe bacteria, which are generally considered to be opportunistic pathogens-causing disease when shrimp are stressed.

Add it to the tank much like you would Indian Almond Leaves, dried or fresh.

Antibacterial + Antifungal – The banana leaf.

Similar to the above guava leaf, but from the banana tree duh.  

9. Parasitic dinoflagellates and ellobiopsids (Ellobiopsidae)

Of which there are thousands of species and many of them are parasitic.  Dinoflagellates and ellobiopsids are major parasites in marine invertebrates and fishes. 

These parasites invade the host’s eggs, digestive tract, soft tissue and blood of the organism, who eventually, succumbs resulting in mortality. They propagate by spores, and if any are seen on your shrimp, care must be take to remove the infected shrimp immediately to minimise the spread to other shrimp.


In freshwater shrimps, the ellobiopsidae appear as green to yellow-green vegetation, reminiscent of a fungal infection.

Often the infected area is between the swimming legs of shrimp and the swimmerettes. It has a mould like appearance.

It’s been mainly seen on shrimps imported from Asia. Possibly from poor water conditions.



Separate infected shrimp immediately.

There is evidence that a dip in formalin (Attention: carcinogenic and toxic!) could be successful.

LINK to our experiment treating green fungus on shrimps – with Helen Ritchie

The following link is to the information written about Shrimp deformity

Disclaimer: The following information and photos have been copied from a thread with permission by the author Jayc of (which is based in Australia) with the proviso that I post the link to the original thread which is constantly being updated.

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