Description
Yellowtail Damselfish (Chrysiptera parasema)
Overview
The Yellowtail Damselfish (Chrysiptera parasema) is a popular choice for marine aquarists due to its striking electric blue body and bright yellow tail. While it is one of the more peaceful members of the Damselfish family, it is still a “damsel” and requires careful consideration regarding tank mates.
- Size: Small, reaching approximately 6–7 cm.
- Lifespan: Often 5+ years with proper care.
- Temperament: Semi-aggressive; more peaceful than other damsels, but can be territorial.
Care Requirements
- Tank Size: Minimum of 100 liters. Larger tanks help diffuse territorial aggression.
- Environment: They thrive in reef aquariums with plenty of live rock. They appreciate having multiple hiding spots (crevices and caves) to establish their own small territories.
- Water Parameters:
- Temperature: 24–28°C (72–78°F)
- Salinity: 1.020–1.025 SG
- pH: 8.1–8.4
Maintenance
Routine maintenance is straightforward for this hardy species but crucial to prevent common issues like ich (a parasitic disease) or fin rot.
- Filtration: Use a protein skimmer, hang-on-back (HOB) filter, or canister filter rated for the tank size. Add activated carbon or chemical media monthly to polish water.
- Substrate and Decor: 5-7 cm of fine sand or aragonite substrate with 10-20 kg of live rock per 100 litres for biological filtration and natural behaviour. Avoid overcrowding—start with 1-3 specimens to establish a hierarchy.
- Cleaning: Siphon detritus during water changes; clean filter media as needed without disrupting beneficial bacteria. Quarantine new fish for 2-4 weeks in a 38-57 litre setup to check for parasites.
- Common Issues: Watch for aggression during feeding or breeding; signs of stress include faded colour or rapid gill movement. Treat ich with copper-based medications (in a hospital tank) or freshwater dips if needed, but avoid in main display if corals are present.
- Lifespan: 5-8 years with proper care; monitor for overfeeding, which can lead to obesity or water fouling.
This fish is forgiving of minor parameter swings but benefits from a mature, stable system.
Diet
These fish are omnivorous and generally have a hearty appetite.
- Feeding: Readily accepts high-quality flake or pellet food. Supplement with frozen foods like mysis shrimp, brine shrimp, and chopped krill to maintain vibrant coloration and health.
- Frequency: Feed 1–2 times daily. They are active hunters and will often pick at algae and micro-fauna on live rock throughout the day.
Behaviour and Compatibility
- Social Dynamics: While more “community-friendly” than the aggressive Domino or Three-Stripe damsels, they can still become territorial, especially toward fish of similar shape or size, or new additions to the tank.
- Tank Mates: Best kept with fish that are of similar or slightly larger size and have a semi-aggressive or confident temperament (e.g., clownfish, blennies, or dwarf angelfish). Avoid keeping them with very timid species (like firefish or small gobies) that may be intimidated or chased.
- Grouping: They can be kept in small groups if introduced simultaneously in a larger tank, though they will establish a hierarchy.
Reproduction
Yellowtail Damselfish are substrate spawners and relatively easy to breed in home aquariums, especially in a species-specific 57-95 litre tank with stable parameters. Breeding success is higher in groups of 1 male to 2-3 females.
- Sexing: Difficult visually; males are slightly larger (up to 6.5 cm) and more intensely blue during spawning, with a more pointed dorsal fin.
- Breeding Setup: Provide flat rocks, PVC pipes, or ceramic tiles as spawning sites. Maintain temperature at 25-26°C and feed protein-rich foods to condition breeders.
- Spawning: Occurs in the evening; the male courts the female, leading her to deposit 200-500 adhesive eggs on the substrate (up to 3 mm diameter). The male fertilises and guards the clutch, fanning it for oxygenation and removing debris. Hatching takes 2-3 days at 25°C, with larvae becoming free-swimming after 3-5 days.
- Rearing: Larvae require rotifers or newly hatched brine shrimp for 7-10 days, then transition to larger foods. Infusoria or greenwater can help. Survival rates are low (10-30%) without experience, but survivors grow quickly.
Tips: Remove the female after spawning to prevent egg-eating. Water quality must be pristine—ammonia spikes can wipe out fry. Bred specimens are hardy and can be sold to local stores.
Tips
- Introduce Last: Because they can be territorial, it is often best to add the Yellowtail Damselfish toward the end of your fish stocking list to prevent it from claiming the entire tank as its territory.
- Aquascape Design: If you notice fighting, rearranging the live rock can disrupt established territories and help reset social dynamics.
- Hardiness: Because of their resilience, they are often used as a “beginner fish,” but be mindful that they are living creatures that deserve a well-cycled, stable environment rather than being used to “cycle” a new tank.
Picture for illustrative purposes only. Either come in store to view available stock or request pictures to be sent to you.
Please Note: Due to variations within species resulting from age, region, sex, etc., the actual livestock may not look identical to the image. Approximate size range may also vary between individual specimens.
