The Lemon Damsel, scientifically known as Pomacentrus moluccensis, is a small, bright yellow damselfish. It's a very common sight on Indo-Pacific reefs and is frequently seen in the aquarium trade due to its vibrant colour, hardiness, and relatively peaceful nature (compared to many other damselfish species).
Here's a comprehensive care guide for the Lemon Damsel:
Appearance:
- Coloration: Almost entirely bright, uniform lemon-yellow all over its body and fins. Occasionally, individuals may have a very subtle blue tint around the eyes or gill covers, especially when stressed or displaying.
- Body Shape: Typical damselfish body shape – somewhat oval and compressed, with a small mouth.
- Size: Small and compact.
Adult Size:
- Lemon Damsels typically reach an adult size of 2 to 3.2 inches (5 to 8 cm) in captivity.
Natural Habitat and Distribution:
- Found widely throughout the Indo-Pacific region, from the Andaman Sea to the Line Islands, north to southern Japan, and south to Australia (including the Great Barrier Reef and waters around Queensland, relevant for Caboolture) and Lord Howe Island.
- Inhabit shallow outer reef slopes, lagoons, and back reefs, usually associating with stony corals like Acropora and Pocillopora. They are typically found in small groups or aggregations, feeding on zooplankton in the water column and detritus.
Aquarium Care (Easy Level):
- Minimum Tank Size: Due to their small size, a minimum of 20 gallons (approximately 75 liters) is suitable for a single Lemon Damsel. For a small group, or a mixed community, a 30-gallon (113 liters) or larger tank is better to provide ample space and help diffuse any potential territoriality.
- Water Parameters: Lemon Damsels are quite hardy and tolerant of a range of conditions, making them a good beginner marine fish. Maintain stable marine water parameters:
- Temperature: 72-82°F (22-28°C)
- Salinity: 1.020-1.025 specific gravity
- pH: 8.1-8.4
- Alkalinity (dKH): 8-12 dKH
- Ammonia and nitrites must be 0 ppm. Nitrates should be kept below 20 ppm.
- Filtration: Standard aquarium filtration is generally sufficient. A good protein skimmer is always beneficial for a marine tank.
- Water Flow: Moderate water flow is suitable.
- Diet:
- Omnivorous: In the wild, they feed on zooplankton, detritus, and some benthic algae.
- In captivity, they are generally eager eaters and readily accept a wide variety of prepared foods:
- High-quality marine flakes and pellets.
- Small meaty frozen foods like mysis shrimp, brine shrimp, cyclop-eeze.
- Vegetable matter, such as spirulina flakes or small pieces of nori, can also be offered as a supplement.
- Feed 2-3 times daily in small amounts.
- Temperament:
- Peaceful (for a damselfish): Compared to many other damselfish species, Lemon Damsels are relatively peaceful. They are still damselfish, however, and can exhibit some territoriality, especially as they mature or if housed in too small a tank.
- Aggression within species: They can be aggressive towards other Lemon Damsels or similar-looking fish, particularly if attempting to keep multiple individuals in a tank that is too small or if they are not introduced simultaneously. Best kept singly or in a larger tank as part of a carefully chosen group (e.g., 5+ individuals to spread out aggression).
- Community Tank: Generally get along well with most other peaceful to semi-aggressive reef-safe fish that are not overly timid or slow-moving. Avoid housing them with overly aggressive or very large predatory fish that might view them as food.
- Reef Compatibility: Excellent reef compatibility. Lemon Damsels are considered truly reef safe. They will not harm corals, clams, or most invertebrates, making them an ideal choice for mixed reef aquariums. They mostly stay in the water column or perch lightly on rockwork/coral branches.
- Tank Setup:
- Provide plenty of live rock with caves and crevices for hiding and establishing territories.
- Ensure ample open swimming space.
- A secure lid is recommended, as damsels can sometimes jump when startled, though they are not as notorious for it as some wrasses or tangs.
- Disease Susceptibility: Generally very hardy and disease-resistant once established. They are often recommended as a good "first fish" to help cycle a tank (though cycling with live rock is more common now).
- Acclimation: Standard drip acclimation is suitable.
- Quarantine: Recommended for new arrivals to observe for health and feeding before introducing them to the main display.
