Rastas Zoa Care Guide
Rastas Zoa is a hardy, photosynthetic Zoanthus colony for reef aquaria. Easy to keep and fast-spreading, but colonies may carry palytoxin and require careful handling.
Compiled by Aquairi from published sources · Published · Updated
Overview
Iconic Rasta zoa morph with red, yellow, and green Jamaica-flag colors. Highly collectible. Zoanthus are colonial anthozoans (often called "button polyps" or "zoas") whose polyps spread to encrust rock with brightly coloured patterns. Their vivid colours come in part from green-fluorescent-protein-like pigments.
Taxonomy
- Family: Zoanthidae
- Order: Zoantharia
- Genus: Zoanthus
- Scientific name: Zoanthus sp. 'Rastas'
- Note: Zoanthus sp. 'Rastas' is an aquarium trade morph of the genus Zoanthus, not a separately described WoRMS species
Habitat
This is an aquacultured Zoanthus morph propagated within the hobby rather than a wild-collected population, so material is sourced from fragmented colonies (Aquacultured).
Tank requirements
- Temperature: 24-26 degrees C
- pH: 8.1-8.4
- Salinity: 1.024-1.026 specific gravity
- Alkalinity: 8-11 dKH
- Calcium: 380-450 ppm
- Magnesium: 1280-1350 ppm
- Lighting: 50-150 PAR (medium), at least 8-12 hours per day
- Flow: low to moderate
- Suggested minimum tank maturity: 3 months
Feeding and lighting
Zoanthus obtain most of their energy from photosynthesis carried out by symbiotic zooxanthellae, so stable lighting is the priority. They can be target-fed about twice weekly with fine phytoplankton or zooplankton and amino acids using a pipette or turkey baster, although supplemental feeding is optional. They are rated among the hardiest, most beginner-friendly corals and tolerate parameter fluctuations.
Placement and compatibility
These passive zoas lack stinging tentacles that threaten neighbours and are considered reef-safe, shrimp-safe and fish-safe. Reef Builders recommends moderate to higher flow to prevent fungal or detritus problems on the mat. Colonies spread quickly by budding, so leave space around them. Reported growth is roughly 0.3-0.8 cm per month under good conditions.
Rastas Zoa: Propagation Guide
Overview
Rastas is a named hobby color morph of the genus Zoanthus (family Zoanthidae), distinguished by red, yellow, and green polyps. Like all named zoas, it is not a separate species but a selected colony of the colonial 'button polyp' corals that hobbyists circulate under trade names. Zoanthus polyps remain connected to one another by a stolon network, or coenenchyme mat, and the genus is known for displaying a large number of color morphs of the same or similar species.
Reproductive Mode
In aquaria, zoanthids are propagated asexually. Colonies form because the offspring of an original polyp remain attached to each other by a fleshy stolon or mat, and new polyps bud along that mat to spread across rock. This budding is the natural growth mode hobbyists rely on; no sexual spawning is needed to expand a Rastas colony.
Fragging / Asexual Propagation
- Select polyps near the colony edge and slice through the stolon mat between them with a clean razor blade.
- Trace the cut line with coral cutters so the section breaks free cleanly; for thick rock bases a diamond band saw is used.
- Soak and dry a frag plug or piece of rubble, dry the base of the cut piece, then apply a small amount of cyanoacrylate glue.
- Press the frag onto the plug, let the glue cure for a few seconds, and return it to the tank.
- The frag is established once it produces new tissue and polyps.
Conditions for Propagation
Zoanthus are among the hardiest and easiest corals to keep, tolerating a range of lighting from lower to higher levels with roughly 8 to 12 hours of light per day. Place healing frags where they receive moderate to higher water flow so nutrients reach the polyps and waste is carried away. Grouped frags can be allowed to expand into a 'garden' as the stolon spreads across the substrate.
Palytoxin Safety
Some zoanthids contain palytoxin, one of the most poisonous non-protein substances known. Wear gloves and eye protection while fragging, avoid touching the face, and wash hands afterward. Never boil, heat, or aggressively scrape rock holding these corals, because heating can aerosolize the toxin and make it inhalable. There is no antidote; only symptoms can be treated.
Common Challenges
Freshly cut polyps may stay closed for several days while the wound heals; stable parameters and gentle flow help recovery. Color intensity of named morphs such as Rastas depends on light and water quality, and slow-growing colonies expand only gradually along the stolon. The main risk in propagation is mishandling palytoxin rather than the cut itself.