Identifying Diseases and Deficiency Symptoms Before It’s Too Late

Is one of your aquarium dwellers acting oddly or looking different? This could be a first sign of disease.

We are going to give you an outline of the most frequent diseases in the aquarium. This will help you limit your initial diagnosis to a few diseases and afterwards select the right medication for the treatment.

About 90 % of all fish diseases can be put down to a weakening of the fish’s immune system. This means the application of remedies can fight the pathogen but doesn’t generally eliminate the cause. It is therefore very important to determine the cause. You can find a list of possible causes here: Aquarium

White Spot Disease / Cryptocaryon

White spot disease is caused by a parasite from the group of the ciliates which can be killed off quickly and safely. No medication can kill the parasite directly off the fish because the parasite is “protected” by the fish’s mucous membrane. This parasite has a life cycle with several stages during which it cannot be killed. Only during a free floating "swarm out" phase is a successful treatment possible. We therefore recommend you raise the water temperature by 3 °C (do not raise the water temperature over 30 °C). This causes the life cycle to be accelerated, which in turn considerably improves the chances of catching the parasite in a vulnerable swarm out phase!

Allthough the white spot disease in marine water completely resembles the white spot disease in freshwater, it is a different pathogen. The disease can also be traced back to a ciliate which carries the name cryptocaryon (sometimes also written cryptocarion).

Product recommendation: JBL Punktol Plus 125 , JBL Punktol Plus 250 , JBL Punktol Plus 1500 , JBL Punktol Red Plus 125

Helps effectively with:

  1. White spots (Ichthyophthirius multifiliis)
  2. Marine white spots (cryptocaryon irritans)
  3. Skin parasite (costia necatrix)
  4. Marine skin parasite (brooklynella hostilis)
  5. Glossatella / heteropolaria
  6. Trichodina heart-shaped skin parasite (chilodonella)

Often confused with: oodinium

Fin Rot / Mouth Rot

These two diseases can be recognised by the fraying, rotting off and later by the complete loss of body parts through this unpleasant looking disease. The disease can be stopped quickly and the fish is able to completely regenerate the body parts affected. To build up sufficient energy reserves for the fish we recommend adding a vitamin product to the food twice a week.

Mouth or fin rot is caused by water quality problems, even if the pathogen is of a bacterial nature. The causative bacteria of the Aeromonas and Pseudomonas group reproduce in the pond very quickly if the water quality is not right. To combat the diseases permanently not only the right remedy but also an improvement of the water quality is necessary. The most important measure is the regular water change. Also the use of a UV-C water clarifier helps to reduce the bacterial germ load in the aquarium and to improve the living conditions of the fish. The most important water values, which need to be checked and if necessary optimised, are: carbonate hardness (KH), pH (pH value), ammonium (NH3) and nitrite (NO2). All you need to know about these water values and how to improve them are to be found in the Water Analysis Online Laboratory . In addition, a thorough and regular cleaning of the filter is recommended.

Product recommendation: JBL Ektol fluid Plus 125

Helps effectively with:

  1. Fin rot (aeromonas, pseudomonas, myxo bacteria and flexibacter)
  2. Columnaris (mouth rot)
  3. Bacterial gill rot

Oodinium

This is a parasite from the group of dinoflagellates (a kind of algae). This means that copper is best suited for combatting oodinum effectively. The copper concentration in the water is decisive in the effort to eliminate this parasite. Exactly 0.3 mg/l of copper are needed, which must then be checked using a suitable copper test. Too much copper can also kill fish, whereas too little copper is ineffective and may even lead to resistant pathogens. Like ichthyophthirius, oodinium has a life cycle where the pathogen passes through different stages. As with the white spot disease, the oodinium pathogen can only be combatted in the swarm out stage. We therefore recommend you raise the water temperature by 3 °C (do not raise the water temperature over 30 °C). This causes the life cycle to be accelerated, which in turn considerably improves the chances of catching the parasite in a vulnerable swarm out phase!

Product recommendation: JBL Oodinol Plus 250

Helps effectively with:

  1. Oodinium pillularis (freshwater velvet disease)
  2. Oodinium limneticum (North American freshwater velvet disease)
  3. Oodinium ocellaris (marine velvet disease)

Often confused with: ichthyophthirius, cryptocaryon

Fungal Infestation

Fungal infections are easily recognisable on fish with their cotton wool-like formations. It is important to start the treatment without delay, as the fungi release toxic metabolic products into the fish organism. This poisoning is actually the main problem. The fish are able to regenerate their skin and any surrounding tissue that have been destroyed quite easily during the healing process. Visible fungal infestation is very often a secondary infection, which may, for example, result from a skin injury. Just as often, though, a bacterial infection which destroys the mucous membrane and the upper skin layers of the fish is found to be the primary cause.

Product recommendation: JBL Fungol Plus 250

Helps effectively with:

  1. Fungal infection (saprolegniaceae)
  2. Spawning-related fungal infection
  3. Water mold (achlya)

Often confused with: mouth rot

External Bacterial Infestation / Open Ulcer

Internal and external bacterial infections can take on a wide variety of appearances. Whitish coatings often appear on the fish skin. However, bloodshot spots can also be discerned or completely different symptoms can occur. A clear diagnosis is only practically possible with a microscope. If a microscope is available, distinguishing between bacterial and parasitic diseases is relatively simple: Most parasites are already clearly recognisable as moving objects with a 100-(!)-fold magnification. By contrast, bacteria are so small that they cannot even be recognised clearly with a 500-fold magnification. To put it simply: If you see objects that are clearly visible and moving around, they are most likely parasites. Conversely, if you don't find anything, you are probably dealing with a bacterial infection.

Product recommendation: JBL Ektol bac Plus 250

Helps effectively with:

  • External bacterial diseases
  • Open ulcers
  • Bloodshot spots
  • Bleedings

Gill Flukes & Skin Flukes & Tapeworms

Rapid breathing, wide open gill cover, apathy and paleness. A low infestation with gill flutes isn’t a problem. A problem only occurs when the worms massively reproduce. This can be only observed in excessively overstocked aquariums or ponds and where there is a lack of hygiene. Another kind of slime formation happens in the gills of the fish if fish are infected with gill flutes. The fish feels the worms in the gills, which anchor themselves there, and tries to get rid of them through slime formation. Unfortunately this doesn’t work and the fish suffocates on its own slime. For gill flutes rapid treatment is advised. The term “monogenic” means that the worms can only reproduce sexually in one host animal. Digenean worms need at least two intermediate hosts to reproduce.

Characteristics of fluke infestation: As with nematode infestation you can observe an emaciation of the fish. They refuse any kind of food and their faeces is often whitish. Health is only damaged during mass reproduction or in small fish. Trematodes have a complicated life cycle with one or several host changes. Snails are usually the first intermediate hosts. It is therefore very useful to remove these intermediate hosts from the aquarium, e.g. with a snail trap. Where required, treatment is possible. But please double-check your diagnosis with a microscopic examination before treatment.

Product recommendation: JBL Gyrodol Plus 250

Helps effectively with:

  1. Gill flukes (dactylogyrus)
  2. Skin flukes (gyrodactylus)
  3. Tapeworms (cestoda)
  4. Flatworms (planaria)

Anchor Worms / Carp Lice

Although this 20 mm long parasite is called a “worm“, it belongs to the crustacean family. It tends to be found in ponds, less in aquariums, in this case on imported wild fish or offspring from field facilities. In the juvenile stages, this parasite can survive for about 5 days without a host. Infection with Lernaea crustaceans weakens the host fish and involves a danger of a fungal or bacterial secondary infection. Please therefore observe the animals after the treatment to verify that the wounds are healing properly. The removal of the crab with tweezers is often recommended. This is not advisable, as the head of the crab is deeply embedded in the fish and stays in the fish when part of the crab is torn off. This then results in poisoning from foreign protein.

The carp louse Argulus is easily recognised on affected fish. It is a parasite; it can grow up to more than one centimetre long, and has a round, flattened body. The carp louse belongs to the fish lice (brachiura) with about 70 crustacean species which live parasitically. They bore into the fish’s flesh to suck blood. Inflammations and infections can occur from the bite. If heavily infested, the fish will also lose weight. Carp lice occur primarily in ponds, but occasionally also in warm water aquarium fish, and when they do it is on imported wild fish or offspring from field facilities.

Product recommendation: JBL Aradol Plus 250

Helps effectively with:

  1. Carp lice (argulus)
  2. Anchor worms (lernaea)
  3. Gill flutes (dactylogyrus)
  4. Woodlice (livoneca)

Worm Infestation

Among the over 10,000 known species of the roundworms (nematodes) especially the screw worm (camallanus cotti) and the hair worm (capillaridae) are well-known in the aquatics. The following general symptoms may indicate one of the aforementioned worm infections: Infected fish become emaciated despite good feeding. The fish occasionally excrete white, slimy faeces, because the parasites damage the intestinal wall, which is then excreted along with the faeces. Please note: Slimy, white faeces can also indicate an improper diet or infection with flagellates. Therefore, this symptom is only a sign of infection with roundworms (nematodes) if it occurs in combination with other of the symptoms mentioned. Schooling fish lose weight and stay outside the school. Individual fish lie on the bottom and make rotating movements. A camallanus cotti infection is relatively easy to recognise: The rear end of the red coloured female hangs out of the after of the infected fish intermittently in order to deposit larvae. With the exception of camallanus cotti, only a microscopic examination can provide a sure diagnosis.

Product recommendation: JBL Nedol Plus 250

Helps effectively with:

  1. Hair worms (capillaridae)
  2. Pinworms (oxuridae)
  3. Camallanus cotti (camallanidae) and nematodes.

Hole-In-The-Head Disease

The hole-in-the-head disease is caused by flagellates of the genus spironucleus or protoopalina. Under specific conditions, which have not yet been clearly defined, there is a mass reproduction of the flagellates which live in the intestine of the fish. They compete with the fish for mineral nourishment and the fish then suffers under mineral deficiency. In response to this deficiency the fish extracts minerals from its own bone tissue. Because the fish’s head has the largest bone substance, it is particularly here that it comes to a massive bone reduction which is visible as holes. The flagellates meanwhile move to the nearest body surface. Because the hole walls are the nearest body surface you can find the flagellates at the bottom of the holes. The flagellates used to be held wholly responsible for this disease. The truth of the matter, however, is that it is a combination of mineral deficiency and the massive reproduction of flagellates which leads to the hole formation. Tapeworms, roundworms, fish tuberculosis and malnutrition can equally lead to hole formation. Remedy: Increase by adding JBL Aquadur the mineral content of the water. So far occurrence of the hole-in-the-head disease has only been observed in very soft water.

Note: Hexamita and spironucleus normally occur in small numbers as harmless fellow occupants in the fish’s intestine. Only when the fish are weakened by other factors, such as inappropriate keeping conditions, deficiency symptoms etc. may these flagellates spread and lead to the death of the fish. Mineral deficiency, which leads to the formation of the mentioned hole-like appearances in the head region, is one reason for that.

Product recommendation: JBL Spirohexol Plus 250

Helps effectively with:

  1. Hole-in-the-head disease
  2. Flagellates (spironucleus, hexamita)

Fish Leeches

These up to 5 cm large leeches attach themselves to the fish skin, suck blood and afterwards cause bacterial and fungal infections. You can’t combat leeches with over the counter medicines. Not even prescription medicines can kill the leeches’ eggs. A mechanical removal of the leech is possible with pincers.

Supplementary Tonic

Supports the treatment against pathogens in the fish’s skin because the salt content of the tonic leads to the regeneration of the mucous membrane.

Product recommendation: JBL Ektol cristal

JBL Online Hospital

Do you have ill fish and you don’t know what disease it is and how to treat it? In the Online Hospital you can diagnose diseases using photos or identification keys and you can find out where they come from and how to treat them. By showing you over 500 photos to identify and cure fish diseases, we enable you to find a diagnosis and solution. The data base there is much larger than the outline given in this article and also contains clear palliative steps.

Try out: Online Hospital

© 08.05.2017
Matthias Wiesensee
Matthias Wiesensee
M.Sc. Wirtschaftsinformatik

Social Media, Online Marketing, Homepage, Kundenservice, Problemlöser, Fotografie, Blogger, Tauchen, Inlineskating, Aquaristik, Gartenteich, Reisen, Technik, Elektronische Musik

About me: Seit Teenagerzeiten mit Aquarien in Kontakt. Klassische Fischaquarien, reine Pflanzenaquarien bis hin zum Aquascape. Aber auch ein Gartenteich und Riffaquarien begleiten mich privat im Hobby. Als Wirtschaftsinformatiker, M.Sc. bin ich als Online Marketing Manager bei JBL für die Bereiche Social Media, Webentwicklung und der Kommunikation mit dem Anwender der JBL Produkte zuständig und kenne die JBL Produkte im Detail.

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