Aquatics - Fungal and bacterial infections

Aquatics - Fungal and bacterial infections

Fungal and bacterial infections

Bacterial infections tend to occur in bad water conditions. Low levels of disease-causing bacteria are always around in the aquarium.


The bacteria and fungus that cause fish diseases are always present in aquariums (although specific species may be introduced with new fish) but will rarely cause a problem if you have good water quality and healthy fish.

Avoiding stress and keeping healthy water conditions are key to avoiding fish disease.  Regularly test your water for abnormalities in ammonia, nitrate, nitrite, pH – and correct any problems, if necessary. 

Poor aquarium hygiene and poor water quality are the key factors in most disease outbreaks.



Cotton wool disease / mouth disease


Mouth Fungus – otherwise known as mouth rot – is caused by Flavobacterium bacteria and is especially common in newly imported fish. 

In the early stages of infection, you’ll probably notice off-white marks around the mouth, fins and body. As the infection spreads, white, fluffy cotton wool-like growths will appear around the mouth and, if left unchecked, the lips start to ulcerate and rot 

Other symptoms include reddened ulcers on the body and frayed fins (Flavobacterium can also cause fin rot). Affected fish will start to ‘shimmy’ as the infection agitates them. They may also go off their food, making them look thin or emaciated. They will usually also show typical signs of stress by clamping their fins to their body going pale and lethargic.


Fin Rot 

Fin rot can be caused by various bacteria including: Aeromonas, Pseudomonas and Flavobacterium. The obvious symptoms of fin rot are split, raggedy or stumpy fins and tail, often with a white edge and red veining. Your fish may suffer from fin rot and cotton-wool disease at the same time; they can be caused by the same bacteria and are encouraged by similar poor water conditions. 

Fungal infections tend to appear when a fish has broken skin. There are several reasons that a fish may have skin damage – as shown in the blue panel above.

If fighting is causing problems, consider re-homing fish that are being aggressive with your existing fish. 



You can treat mouth fungus and fin rot with Anti Fungus and Finrot to attack the bacteria. You can also support the health of your fish by using Aquilibrium First Aid Salt with the treatment. 


Treatment and Salt 


Key features

  • Treats affected fish
  • Prevents the disease spreading for a healthier aquarium
  • Product overview

    They might be common diseases, but it doesnt make finrrot, mouthrot and cotton wool disease any less harmful. Minimise the problem with Anti Fungus and Finrot. This antibacterial and antifungal treatment will treat affected fish and prevent the disease from spreading in your aquarium. Use for treating against mouth rot (Columnaris sp.), fin rot (Psuedomonas sp) and cotton wool (Saprolegnia sp.) fungus. *Shake well before use*


    Key features

    • Reduces physiological stress for healthier fish
    • Stablises water quality to support your aquarium's balance

    Product overview

    This must be one of the most helpful treatments for any aquarium-keeper to have on-hand.
    A healthy salt/fluid balance is crucial to a fish's wellbeing. When stressed or sick, the salt/fluid balance can be disturbed which further threatens the fish's health.
    Aqualibrium First Aid Salt is a unique physiological salt formula which helps freshwater fish maintain a constant internal salt-fluid balance.
    Aqualibrium First Aid Salt additive is an incredibly versatile water treatment and can be used in a number of ways:

  • As a general aquarium tonic
  • As a mild pH buffer
  • To help minimise the physiological effects of stress on your fish
  • As a supportive measure when treating diseases
  • To reduce the toxicity of Nitrite
    Use to support your aquarium community's immune system to minimise the effcts of fish stress and when using medical treatments.



    Share this post...

    Previous post Next post