Tongan Longspine Cardinalfish

The Tongan Longspine Cardinalfish (Apogon sp.) is a peaceful species that is reef-safe with caution, admired for its elongated spines, striking body patterns, moderate size, and nocturnal behavior. Males typically develop longer spines and engage in mouthbrooding to protect eggs, while females and juveniles have shorter spines and a more streamlined appearance. They reach about 3 to 4 inches in length and should be housed in aquariums of at least 30 gallons.

Provide a sandy substrate with plenty of live rock, caves, and hiding spots, stable water parameters (salinity ~1.020–1.025, temperature ~72–79°F, pH ~8.1–8.4), and a secure lid since many cardinalfish species are prone to jumping.

Diet should consist of mysis shrimp, brine shrimp, copepods, and high-quality marine pellets or frozen foods. With proper care, this fish makes a captivating and peaceful addition to marine 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.