Radioactive dragon eyes

Radioactive dragon eyes is a zoanthid morph listed as Zoanthus sp., one of the classic named zoanthid color forms. A settled colony grows as a mat of connected polyps over rock or a frag plug, each polyp opening as a round disc on a short stalk. The name follows the bright, glowing green face each polyp carries, a vivid center that seems lit from inside under blue light, framed by a darker skirt of lashes around the rim. Few zoanthids read as clearly across a room, and the contrast between the glowing face and the dark fringe is the mark to identify the morph by.

The entry lists beginner care, medium light, medium flow, middle placement, peaceful behavior, and moderate growth. The original notes add a practical warning: keep the colony off the sand and check new frags for zoanthid pests. Place the frag in the middle of the rockwork on solid rock, with room for the mat to spread. Medium light holds the bright green face at full strength. Polyps kept in deep shade stretch on long stalks and dull, while a sudden move into very strong light can keep the mat closed for days.

Medium flow should pass over the mat in a broad, changing pattern. Moving water keeps detritus and film from settling between the polyps, which is where closed, unhappy zoanthids usually start. A direct jet can keep one edge of the mat shut. Gentle movement that rocks the lashes slightly is plenty, and the colony opens widest when waste never gets the chance to sit on it.

Feeding is indirect and simple. Zoanthids draw much of their energy from light, and the polyps also take fine particulate food from regular broadcast feeding in a fed reef tank. Present, steady nutrients suit this morph well. Very clean, stripped water can shrink polyp size and slow the mat, while heavy target feeding mostly fouls the rock around the colony. A normal reef feeding routine covers its needs.

This morph is listed as peaceful, with no sting worth planning around. Spacing is about spread and contact. A growing mat advances over the rock it touches and can crowd the base of a slower neighbor, and a stinging coral placed against the mat will damage polyps on contact. Give the colony its own rock face or an island it can cover, with a couple of inches of clearance from corals that sting, and trim the edge back if the mat heads toward a prized frag.

Growth is listed as moderate. New polyps bud around the rim of the mat, the edge creeps outward, and a small frag can cover its rock over a season in a stable tank. Polyps that stay closed for many days, a mat that melts at one edge, or stalks that stretch tall and thin usually point to a pest, film on the mat, or a light level the colony dislikes. A freshwater or coral dip check and a close look for nudibranchs or spiders is the standard first response to a closing mat.

Palytoxin caution: zoanthids can carry palytoxin. Handle the colony with gloves, keep it away from cuts, wash hands after contact, and never boil, steam, or pressure-wash zoanthid rock, because heat and aerosols can carry the toxin. Work on the colony outside the tank where possible and keep the water used for rinsing away from food areas.

Common pitfalls include burying the mat edge in sand, skipping a dip and inspection on a new frag, and placing the colony in a dead corner where film settles between polyps. Start on clean rock in the middle of the tank, dip and inspect first, and let full, flat opening confirm the spot.

Field notes — what keepers report

- Color reports agree on the glow. Keepers describe the green face reading brightest under blue-leaning light at medium intensity, and a duller, browner face from colonies kept shaded under an overhang. Keepers who moved a shaded mat up in stages describe the glow returning over a few weeks.

- Pest reports carry the main warning. Keepers describe new, uninspected frags closing within weeks from zoanthid-eating nudibranchs or spiders, and other keepers describe years of clean growth from frags that were dipped and checked on arrival. Inspection at the door is the shared practice across both kinds of report.

- Growth reports split by tank feeding. Keepers in fed tanks describe a mat that spreads steadily and covers its rock, while keepers in very clean systems describe polyps holding on at a slower pace with smaller discs. Both sides describe the morph as forgiving of ordinary swings once settled.