Utter Chaos
Zoanthus sp.
Species profile
Cobalt
Zoanthus sp.
Also sold as: Cobalt zoa, Cobalt zoanthid
Cobalt is a zoanthid with a glowing cream-white center, a cobalt blue-violet face and olive-green tentacles.
Colors
Glowing white to cream center around a small mouth; a deep cobalt to violet-blue disc with fine radial lines; and olive-green tentacles with a yellow tint
Care at a glance
Care level
Easy
Light
Medium
75-150 PAR
Flow
Moderate
Growth rate
Moderate
Placement
Lower to middle rockwork, ideally a spot near the front of the tank where the cobalt faces can be seen up close
Temperature
75 to 80°F (24 to 27°C)
Salinity
1.024-1.026 specific gravity (about 32-35 ppt)
Feeding
Mostly light-fed, with optional fine foods once or twice a week.
Photosynthetic; optional fine particulate food once or twice a week
Care notes
The face is a deep cobalt to violet-blue, with a glowing cream-white center and a ring of olive-green tentacles. Under strong blue light the colors look more intense, and under whiter light they look softer. Care values here are typical for zoanthids, not measured for this morph: medium light, moderate, indirect flow and steady water. Give a new frag time to settle before judging its growth or color, and if it starts to pale, move it lower rather than changing several things at once. Zoa trade names are used loosely, and colonies sold under this name can look different, so buy from photos of the actual colony.
⚠ Palytoxin safety
Like any zoanthid, Cobalt may contain palytoxin, so treat it as toxic. Wear gloves and eye protection when handling or fragging, and wash up afterward.
