Yellow Tail Cardinalfish

The Yellow Tail Cardinalfish (Apogon sp.) is a peaceful species that is reef-safe, admired for its subtle body coloration contrasted by a vibrant yellow tail, small size, and nocturnal habits. Males typically display brighter tail coloration and may be observed mouthbrooding fertilized eggs, while females and juveniles are slightly less colorful and tend to school more frequently. They reach about 2 to 2.5 inches in adult size and should be housed in aquariums of at least 20 gallons, ideally in small groups for natural behavior.

Provide plenty of live rock for hiding spots, along with some low-flow areas and dim lighting to mimic their natural reef habitat. Stable water parameters are essential: salinity around 1.020–1.025, temperature between 72–79°F, and pH around 8.1–8.4. A secure lid is highly recommended as they are prone to jumping when startled, especially at night.

Their diet should consist of small meaty foods such as mysis shrimp, brine shrimp, copepods, and finely crushed pellets or flakes. With proper care, the Yellow Tail Cardinalfish makes a calm, attractive, and hardy addition to peaceful community and reef aquariums.

International Aquatics Quarantine & Guarantee: All fish are checked by marine vets, given a formalin bath, and held for 14 days in copper-treated systems. We feed Selcon-soaked food with Kanaplex and Metroplex during quarantine. Unless marked, all livestock comes with our 15-Day Guarantee. You will receive a video of your fish eating before shipment. On request, we also send photos/videos after arrival at IA. Some species are import-to-order (3-10 business days). Many common species are already cleared or near the end of QT.

Several species will be import-to-order and may take anywhere from 3-10 business days to secure. Once your fish is secured, you will be notified, and the quarantine process will then begin.