Frogspawn coral

Geographical Origin & Biotope:

The Frogspawn Coral (*Euphyllia divisa*) is an immensely popular, beautifully structured Large Polyp Stony (LPS) coral natively endemic to the warm, shallow reef crests, sheltered lagoons, and turbid coastal waters of the Indo-Pacific Ocean, Fiji, and the Great Barrier Reef. Their natural biotope is defined by environments with moderate, chaotic water flow and strong sunlight, where they form massive colonies that shelter numerous species of reef fish and invertebrates.

Taxonomy & Morphology:

Scientifically classified within the Euphylliidae family, they are an LPS coral characterized by a massive, calcified, arborescent (branching) or wall-like skeleton. Morphologically, they are globally recognized by the unique shape of their fleshy tentacles. Defining Feature: Unlike the single-tipped Torch Coral, the tentacles of the Frogspawn branch out laterally, covered in multiple rounded, bulbous nodules that look exactly like a mass of translucent frog eggs.

Social Behavior:

They are sessile but highly aggressive and territorially dominant invertebrates. Like all *Euphyllia* species, they fiercely defend their space. CRITICAL BEHAVIOR: During the night (and occasionally during the day), the Frogspawn will extrude transparent, ultra-long "sweeper tentacles" capable of reaching up to 6 inches (15 cm) away. These sweepers are armed with extremely potent nematocysts that will instantly sting, burn, and dissolve the tissue of competing corals.

Coloration & Sexual Dimorphism:

Sexual dimorphism is non-existent. Their coloration is vibrant, complex, and highly desirable in the reef aquarium. The thick, multi-branched tentacles are typically a translucent, fleshy pink, beige, or rich brown. The true visual spectacle lies in the bulbous "frog egg" nodules, which aggressively present in blinding neon green, electric pink, vivid purple, or glowing yellow. Under blue actinic lighting, the tips of the tentacles radiate intense fluorescence.

Tank Setup:

The aquarium architecture MUST accommodate their highly aggressive nature and need for physical space. A minimum 110-liter (30-gallon) marine aquarium is strictly required. CRITICAL REQUIREMENT: Provide absolute isolation. Leave a massive perimeter of empty space (at least 6 inches / 15 cm) around the coral to ensure its deadly sweeper tentacles cannot reach and assassinate neighboring corals. Securely glue the skeletal base to the live rock to prevent falls.

Diet & Feeding:

They are robustly autotrophic, utilizing their symbiotic zooxanthellae to convert intense aquarium lighting into daily energy. However, they are also ferocious, highly capable predators. While target feeding is not strictly mandatory for survival, it is highly recommended. Gently target feeding the polyps 1-2 times a week with thawed Mysis shrimp, Krill, or LPS-specific sinking pellets will result in explosively fast skeletal growth and magnificent polyp extension.

Water Quality:

As heavily calcified, demanding LPS corals, they require impeccable and highly stable water chemistry. They demand stable tropical heat (24-27°C / 75-81°F) and salinity between 1.024 and 1.026. CRITICAL REQUIREMENT: They MUST be provided with pristine Calcium (420-450 ppm), Alkalinity (8-10 dKH), and Magnesium (1300-1400 ppm) levels to synthesize their heavy calcium carbonate skeletons. Rapid fluctuations in Alkalinity will cause the coral to eject its fleshy polyps (polyp bailout).

Compatibility & Tankmates:

Compatibility requires careful, strategic mapping of the aquarium. They are deadly to SPS corals, most soft corals, and unrelated LPS corals. Fascinating Exemption: Frogspawn Corals are generally completely immune to the stings of other Frogspawn Corals and Hammer Corals (*Euphyllia ancora*). Aquarists frequently place these species right next to each other to create a massive, multi-colored *Euphyllia* "garden" without any warfare. They are a beloved surrogate host for Clownfish.

Aquarium Breeding:

Propagating (fragging) the Frogspawn Coral is simple but depends on its skeletal structure. If it has a "branching" skeleton, aquarists can easily use bone shears or a Dremel to cut off a dead, calcified branch well below the fleshy tissue. CRITICAL WARNING: If the coral is a "wall" variant (a continuous, solid, meandering skeleton), fragging is highly dangerous and requires cutting through live fleshy tissue with a diamond bandsaw, which carries a massive risk of lethal infection.

Risks & Diseases:

CRITICAL DISEASE RISK: They are extremely vulnerable to "Brown Jelly Disease" (BJD), a fast-acting bacterial/ciliate pathogen that turns the coral's flesh into a rotting brown slime, capable of killing the coral in hours. The second risk is physical tissue tearing; placing the coral in water flow that is too strong or direct will violently thrash the fleshy polyps against the razor-sharp skeletal ridges, causing severe lacerations, subsequent bacterial infection, and death.