Zoanthus

Zoanthus, affectionately known as zoas, are among the most collected corals in the reef hobby thanks to their astonishing variety of colour combinations and patterns. They form dense colonies of small polyps that carpet rockwork in vibrant mats. Named designer morphs — with creative names like Eagle Eye, Fruit Loop, and Utter Chaos — command premium prices, while common varieties are extremely affordable. Place zoas in the mid-section of your tank under moderate PAR (75–200 PAR) with moderate flow. Standard reef parameters work well: alkalinity 7.5–9 dKH, calcium 400–440 ppm, and temperature 25–27°C.

Zoanthus are photosynthetic and generally undemanding, though their colours can shift under different lighting. Many collectors find that medium-intensity blue-heavy LED lighting brings out the most vivid fluorescent colours. Zoas do not require target feeding but will benefit from broadcast feeding with fine coral foods, which can accelerate colony growth. If polyps stay closed for extended periods, check for pests — zoanthid-eating nudibranchs (tiny, well-camouflaged slugs) and sundial snails are the most common culprits. Dip all new zoa additions in CoralRx or similar before adding to your tank.

Fragging zoanthids is straightforward — use a sharp scalpel to cut small groups of polyps from the mat, along with a small piece of the substrate they are attached to. Superglue the frag to a plug and keep it in moderate flow while it recovers. Zoas are the backbone of the Australian coral trading community, with dedicated collectors building impressive gardens of rare morphs. Reef expos and local frag swaps are excellent places to find new varieties at reasonable prices.