In coral reef aquariums, the health of both corals and fish is crucial. While corals are not prone to as many diseases as fish, they can still face various issues. Here are some of the most common coral reef aquarium diseases and conditions:

Coral Bleaching

Not a disease per se, but a stress response to environmental changes such as high water temperatures or changes in light intensity. Corals expel their symbiotic algae, causing them to turn white. If prolonged, it can lead to coral death.

Rapid Tissue Necrosis (RTN) and Slow Tissue Necrosis (STN):

These conditions involve the rapid or slow death of coral tissue, leading to tissue recession. The exact causes are complex, often involving stress, pathogens, or poor water quality.

Brown Jelly Syndrome:

Affects soft and stony corals, where a brown, jelly-like substance covers and consumes coral tissue. It’s often a sign of tissue necrosis and can be caused by various factors.

Coral Pests:

Some pests like flatworms, nudibranchs, and certain snails can consume coral tissue, leading to damage and death.

Coral Tumors:

Abnormal growths on coral tissue, often occurring due to stress or injury. The causes and mechanisms behind coral tumors are still not completely understood.

Coral Fungal Infections:

Similar to fungal infections in fish, corals can also be affected. Fungal infections can lead to tissue discoloration and decay.

Cyanobacterial Blooms:

Also known as red slime algae, cyanobacteria can overgrow corals, suffocating them and causing tissue recession.

White Band Disease (WBD):

Affects branching corals like Acroporas, causing the death of tissue along the coral’s branches, leaving behind a white band.

Black Band Disease:

A bacterial infection that forms a dark band on the coral, which slowly migrates and consumes live tissue.

Stony Coral Tissue Loss Disease:

A relatively new and concerning disease that affects multiple coral species, causing rapid tissue loss and mortality. Its exact cause is under investigation.

Preventing coral diseases involves maintaining stable water parameters, providing proper lighting, good flow, and avoiding stressors. Quarantining new corals and practicing proper tank hygiene can also help prevent disease introduction. If you suspect a disease outbreak, consult with a knowledgeable reef aquarium expert or a coral disease specialist for guidance.