Bacterial Ulcers
Aeromonas / Pseudomonas
High severity
open red sores from opportunistic bacteria, usually on fish weakened by poor water or injury
Symptoms
Catching illness early gives the best chance of recovery, so check your fish daily. Open red sores or ulcers on the body, raised or missing scales, reddened edges, and lethargy. In bad cases the ulcer deepens into the muscle. Act promptly if you see several signs together.
Causes
Gram-negative bacteria infecting damaged skin, usually on fish weakened by poor water quality, injury, rough handling or other disease. The underlying trigger is almost always stress, poor water quality or a newly introduced animal.
Treatment
Isolate the fish, improve water quality, and treat with a broad-spectrum antibacterial (medicated food is best for systemic cases). Clean, stable water is essential for the ulcer to heal.
While treating, increase aeration, remove activated carbon from the filter, finish the full course even after symptoms fade, and keep the water immaculate. Marine treatments belong in a separate quarantine tank, never the reef.
Prevention
Maintain excellent water quality, avoid injury and sharp decor, and quarantine new fish to prevent the bacteria taking hold. The golden rules: quarantine new arrivals, never overstock or overfeed, avoid sudden swings, and keep up regular water changes.
FAQ
What is Bacterial Ulcers in fish?
How serious is Bacterial Ulcers?
How do I treat Bacterial Ulcers?
Can Bacterial Ulcers be prevented?
Will it spread to my other fish?
This information is general guidance, not veterinary advice. Consult an aquatic vet for serious cases.