Palythoa Coral Care Guide

Palythoa coral contains palytoxin, one of the most potent natural toxins known to science, which can cause serious illness through skin contact, eye exposure, or inhalation of aerosolized particles. The CDC documented multiple cases of aquarists hospitalized with symptoms including respiratory distress, muscle pain, fever, and cardiac complications after handling Palythoa without protection or boiling live rock containing Palythoa colonies.

Reef keepers must always wear nitrile gloves and safety glasses when handling Palythoa, work only with submerged specimens to prevent aerosolization, and never boil, scrub, or use hot water on rocks containing Palythoa polyps. Anyone experiencing symptoms after Palythoa exposure should seek immediate emergency medical care.

Palythoa coral has larger polyps measuring 0.5-1 inch in diameter with a slit-shaped mouth, while Zoanthid polyps are smaller with a round mouth surrounded by a distinct sphincter muscle. Palythoa tissue incorporates sand and sediment particles into its structure creating a coarse texture, whereas Zoanthid tissue remains smooth and tears more easily.

Palythoa colonies typically display more muted colors like brown, cream, and green compared to the vibrant rainbow patterns common in Zoanthids, though fluorescent Palythoa morphs do exist. Both genera require similar care conditions and contain varying levels of palytoxin, so identification primarily matters for aesthetic preferences rather than husbandry adjustments.

Palythoa coral spreads aggressively across rock surfaces and can overtake entire aquascapes if left unchecked, with some species capable of covering overflow boxes and back glass within weeks. Reef keepers should place Palythoa colonies on isolated rock islands or removable frag plugs rather than directly on the main aquascape to prevent uncontrollable spreading.

Trimming Palythoa colonies regularly with scissors while wearing protective gloves prevents overgrowth, and maintaining physical gaps between Palythoa and slower-growing corals protects valuable specimens from being smothered. Planning for eventual removal is essential since large Palythoa mats become extremely difficult and hazardous to extract safely.

Palythoa coral remaining closed typically indicates lighting that is too intense, excessive direct water flow, water parameter fluctuations, or the natural mucus-shedding process that occurs periodically. Palythoa grandis in particular prefers lower lighting and will close when lights reach peak intensity, reopening during dimmer periods of the photoperiod.

Reef keepers should check for pests including sundial snails, zoanthid-eating nudibranchs, and zoa spiders that can irritate Palythoa polyps. Palythoa colonies sometimes remain closed for several days while shedding their outer mucus layer, which is normal behavior that resolves without intervention.

Palythoa coral obtains nutrition primarily through photosynthesis but actively captures food particles from the water column when tentacles are extended. Supplemental feeding with powdered coral foods like Reef-Roids, frozen cyclops, or liquid coral foods accelerates Palythoa growth and enhances color vibrancy, though feeding is not required for survival.

Palythoa coral feeds most readily when polyps are fully extended, typically during evening hours or when food is detected in the water. Target feeding individual polyps with a pipette produces better results than broadcast feeding, which can contribute to excess nutrients and algae growth.

Palythoa coral thrives under low to moderate lighting between 50-150 PAR, making Palythoa suitable for lower and mid-tank placement where light-demanding corals would struggle. Some Palythoa species like Palythoa grandis prefer lighting at the lower end around 50-100 PAR and will remain closed under intense illumination.

Reef keepers should position Palythoa colonies where they receive consistent indirect lighting without exposure to the strongest areas directly under LED pucks or metal halide bulbs. Palythoa adapts to various lighting spectrums and does not require specific color temperatures for health, though blue-heavy spectrums enhance fluorescent coloration in some morphs.