Furunculosis

Furunculosis

Furunculosis Disease in Freshwater Tropical Aquarium Fish

Below is the format overview we follow and how we present the information.

UPDATED: July 2, 2026

Identification

Can be all, any number, or only one from the list:
Boils on the skin that ooze puss.
Lesions on the skin.
Fins become red inflamed and start to fray.
Red Hemorrhages presenting on the skin, fins, gills and internallly.

CLASS

Bacterial Gram -

Reproduction

Material that oozes from the boils and lesions.

Causes

When fish consume fecal matter from infected fish (live foods) and skin parasites.
Material that oozes from the boils and lesions.
Poor water Quality and poor husbandry foster the outbreak.
The fish are at risk from starvation, malnutrition, improper diet, incomplete diet, cold, stress from transport, unsanitary condition in tanks that burden their processes.

Treatments

Disinfecting tank, equipment, decorations, rock the whole works.
Treat with a gram negative antibiotic.
Furan, Tetracycline, Chloramphenicol

Observations, Notes, Remarks

This bacteria is an Aeromonas.
Fungus is a quickly occurring secondary infection.
Affects internal organs.