Threadfin Cardinalfish
Apogon leptacanthus
Saltwater Fish
Species Group: Cardinalfish
Family: Cardinalfish
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Water parameters
Temp
76-80 F
Temperature
Maintaining a stable and appropriate temperature is critical for the survival of aquatic life.
pH 7.8 - 8.4 potential of HydrogenMeasuring the acidity or alkalinity of water on a 0–14 scale, where 7 is neutral, 7 is alkaline.
NO3 1-20 ppm NitrateWhile less toxic than ammonia, high nitrate levels (above 40–80 ppm) are important to monitor because they can cause fish stress, stunted growth, and harmful algae blooms.
NO2 <0.0001 ppm NitriteIt is a highly toxic, intermediate compound in the nitrogen cycle produced from broken-down ammonia
PO4 0.01 - 0.1 ppm PhosphateIt is essential for plant development but must be managed, as excess levels trigger nuisance algae blooms and inhibit coral calcification.
NH3 <0.1 ppm AmmoniaIt is the primary killer of aquarium fish, causing gill damage, stress, and death
Ca 380 - 450 ppm CalciumSupporting the growth, skeletal structure, and shell formation of corals, mollusks, crustaceans, and coralline algae
KH 8 - 12 dKH AlkalinityIt acts as a shield, neutralizing acids to prevent dangerous pH "crashes" that can harm fish, corals, and plants.
Mg 1200 - 1400 ppm MagnesiumIt enables coral growth by supporting skeletal formation, assists in metabolic processes, and ensures that calcium is available for corals, clams, and coralline algae.
SG 1.023 - 1.026 SG SalinityEssential for maintaining stable, natural water parameters, proper osmoregulation, and stress-free environments for marine fish and corals
ORP 250 - 400 mV Oxidation-Reduction PotentialA higher positive mV indicates clean, oxygen-rich water with high water quality, while low readings indicate high pollution.
About Threadfin Cardinalfish
General information
Threadfin Cardinalfish is a small and peaceful fish species, typically growing to an average length of 3 inches (7.5 cm). These fish are popular in the aquarium trade due to their bright colors and ease of care. They are native to the Indo-Pacific region, specifically in reefs from the East African coast to the Hawaiian Islands.
Diet & nutrition
In the wild, Threadfin Cardinalfish feed on small invertebrates and plankton. In captivity, they will readily accept a diet of small meaty foods such as brine shrimp, krill, and chopped pieces of marine fish. It is recommended to feed them small portions several times a day rather than one large meal.
Determining sex
It can be difficult to determine the sex of Threadfin Cardinalfish as males and females look very similar. However, during breeding season, males may exhibit brighter colors and a more elongated dorsal fin.
Breeding & spawning
Threadfin Cardinalfish are egg-layers and have been successfully bred in captivity. They are typically monogamous and will pair up during breeding season. The female will lay several hundred eggs on a flat surface and the male will guard and fan the eggs until they hatch in 4-5 days.
Diseases
Threadfin Cardinalfish are generally hardy and disease-resistant when kept in suitable water conditions. However, they can be susceptible to common aquarium diseases such as ich, marine velvet, and bacterial infections.
Origination
Threadfin Cardinalfish are native to the Indo-Pacific region, specifically in reefs from the East African coast to the Hawaiian Islands.
Cautions
Threadfin Cardinalfish are generally peaceful and can be kept with other non-aggressive species. However, they may become territorial during the breeding season.
Acclimation process
When introducing Threadfin Cardinalfish to a new aquarium, it is important to acclimate them slowly to avoid shock. Float the sealed bag in the aquarium for 15-20 minutes to allow the water temperature to equalize. Then, open the bag and add small amounts of aquarium water to the bag over the course of 1-2 hours. After acclimation, release the fish into the aquarium.
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