Vibrio is a lactose-fermenting, gram-negative, slightly curved and rod shaped bacteria, opportunistic pathogen, and is found in aquatic environments. Vibrio is genearally more common in Brackish or Saltwater. This organism causes wound infections, gastroenteritis, and is a common cause of ?hemorrhagic septicemia?, where the microorganism enters the blood stream, resulting in septic shock, rapidly followed by death in many cases (about 50%).

A common symptom in marine fish and brackish fish is red patches or red streaked fins, especially in Yellow Tangs and Marine Angels.

Kanamyacin is very effective in the high pH applications where Vibrio is usually present. Another older but useful antimicrobial for treatment of Vibrio is Triple Sulfa and it also is effective in high pH environments.

Pimafix and a tea made Usnea Lichen are natural treatments that have shown effectiveness for Vibrio.

Treatment of wounds with Mebromine or a 30 minute double dose dip with Methylene Blue is also useful in treatment of Vibrio.

One of the most common infections in freshwater fish is caused by the rod-shaped bacteria Aeromonas, which is also a gram negative, lactose-fermenting bacterium.

Aeromonas is another common cause of hemorrhagic septicemia, especially in freshwater. This disease is common in goldfish and many Tropical Fish. Affected fish usually have shallow or deep ulcers somewhere on the body, but may exhibit other signs such as exophthalmia (pop-eye), areas of bloody spots, and a distended abdomen. Infected fish with open sores appear to spread the disease to other fish, and sub clinical carriers may exist, shedding bacteria in their feces.

Aeromonas infections are probably the most common bacterial disease to infect Tropical Freshwater Fish. Mortality rates are often low (10% or less) and losses may occur over a period of time (2 to 3 weeks or longer). In these instances, some factor; usually stress, has caused the fish to become more susceptible to the bacteria. Common sources of stress are poor water quality, overcrowding, or rough handling.

In Coldwater freshwater fish the similar pathogen is Aeromonas salmonicida also known as furunculosis. Treatment in Coldwater can be difficult as many treatments are not as effective below 65 degrees F. Also Nirofurazone, which is one of the treatments of choice in coldwater, is less effective at the higher pH most coldwater fish prefer. Nirofurazone is also very useful in Discus and other Amazon River fish applications due to its increased effectiveness at lower pH. In higher pH applications Triple Sulfa and Kanamyacin can also be effective. And on some strains of Aeromonas, Tetracycline has shown occasional effectiveness.

Another treatment in coldwater is Oxytetracycline, which works much better if soaked in the food and is especially useful when treating the water such as in a pond is undesirable.

A newer treatment preferred by many Koi keepers is KoiZyme (formally known as LymnoZyme). This is a formula of natural bacteria, enzymes, and micro nutrients that reduce the Aeromonas (and Pseudomonas) bacteria present in the water. It does not attack the bacteria directly, rather is out competes the Aeromonas bacteria for nutrients.

Melafix is an organic treatment shown to be effective for Aeromonas, especially in pond applications. Treatment of wounds with Mebromine or a 30 minute double dose dip with Methylene Blue is also useful in treatment of Aeromonas.

It is important to note that both Aeromonas and Vibrio pathogens are opportunistic bacteria that are more virulent in poor water conditions.

It is important to effect a cure that water conditions are improved during treatment and not worsened by the treatment itself, which is why I do not recommend Tetracycline, be used in display tank treatments of this disease as Tetracycline lowers red blood cell counts and binds calcium in the water which is essential for healing. Regular partial water changes between treatments, proper pH and a proper functioning bio filter are all essential for effective cure.

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