Common name: Spiny Chromis

General Information

The Spiny Chromis, scientifically known as Acanthochromis polyacanthus, is a fascinating species of damselfish that stands out due to its unique breeding behavior. Unlike most marine fish that release their eggs into the water column, the Spiny Chromis is known for its parental care, as both parents guard their eggs and fry, providing a rare glimpse into fish family dynamics. This makes them particularly interesting to both hobbyists and researchers alike.

In the aquarium trade, the Spiny Chromis is appreciated for its hardiness and adaptability, making it a suitable choice for both novice and experienced aquarists. Its role in the hobby is significant, as it provides an opportunity to observe complex social behaviors and breeding habits in a captive setting.

Physically, the Spiny Chromis is characterized by its elongated body, spiny dorsal fin, and a color palette that ranges from shades of brown to a subtle blue-green sheen, depending on lighting and mood. This species can be easily distinguished from other damselfish by its lack of a caudal fin fork and the presence of numerous spines on its dorsal fin.

Care

Spiny Chromis are relatively easy to care for, thriving in a variety of tank conditions. They prefer aquariums with plenty of live rock for hiding and exploring. A tank of at least 120 liters (30 gallons) is recommended to provide ample space for swimming and territory establishment.

To create a stimulating environment, include a variety of rock formations and hiding spots. This not only mimics their natural habitat but also provides them with security and reduces stress.

Diet and Feeding

In the wild, Spiny Chromis are omnivorous, feeding on plankton, algae, and small invertebrates. In captivity, they should be offered a balanced diet that includes high-quality flakes or pellets, supplemented with frozen foods such as brine shrimp and mysis shrimp.

Feed them once or twice daily, ensuring they consume all food within a few minutes to prevent overfeeding and maintain water quality.

Behavior and Compatibility

Spiny Chromis are known for their peaceful temperament, making them ideal candidates for community aquariums. They exhibit interesting social behaviors, often forming small schools that add dynamic movement to the tank.

While generally non-aggressive, they can become territorial, especially during breeding. It's advisable to keep them with other peaceful species to maintain harmony in the tank.

Reproduction

One of the most intriguing aspects of Acanthochromis polyacanthus is its breeding behavior. Unlike many marine fish, Spiny Chromis do not undergo a pelagic larval stage. Instead, parents fiercely guard their eggs and fry, which are laid on a flat surface within their territory. This species provides a unique opportunity to observe parental care in a marine setting, making them a rewarding choice for aquarists interested in breeding.

Health and Common Issues

Spiny Chromis are hardy fish, but they require stable water conditions to thrive. Regular tank maintenance, including water changes and monitoring of water parameters, is essential to prevent common health issues.

Look for active, healthy individuals when purchasing, avoiding those with visible signs of disease or stress. Ensure a balanced diet to maintain their vibrant colors and overall health.

Habitat

Native to the Indo-Pacific region, the Spiny Chromis is commonly found in coral-rich lagoons and outer reef slopes. They inhabit areas with abundant coral and rocky substrates, which provide ample hiding spots and feeding grounds.

In captivity, replicating these conditions with live rock and coral decorations can help them feel at home and exhibit natural behaviors.