Speckled Krakatoa Zoa Care Guide
A slow-growing Zoanthus morph with a speckled green skirt and a red volcano-like center; a photosynthetic encrusting zoanthid for reef tanks.
Compiled by Aquairi from published sources · Published · Updated
Overview
Speckled Krakatoa Zoa is a named color morph of Zoanthus, a colonial zoanthid in the family Zoanthidae. The morph shows a speckled green skirt around a red, volcano-like center, and is a relatively slow grower. Zoanthids form colonies of small polyps that spread across rock as an encrusting mat and are commonly called zoas or button polyps.
Taxonomy
- Phylum: Cnidaria; Class: Anthozoa (Hexacorallia); Order: Zoantharia
- Family: Zoanthidae
- Genus: Zoanthus Lamarck, 1801
- Scientific name: Zoanthus sp. 'Speckled Krakatoa' (aquacultured designer morph)
Biology
Zoanthus is a zooxanthellate genus: the polyps host symbiotic algae (zooxanthellae) and obtain most of their energy from photosynthesis, supplemented by capturing fine food particles with their tentacles. Polyps are connected by shared tissue and reproduce asexually by budding, allowing a colony to spread over a rock surface.
Tank requirements
- Salinity: 1.024-1.026
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Alkalinity (dKH): 8-11
- Calcium: 380-450 ppm
- Magnesium: 1280-1350 ppm
- Nitrate: below ~15 ppm; Phosphate: below ~0.1 ppm
- Lighting: medium, around 50-150 PAR
- Flow: low to moderate (enough to keep detritus off the polyps)
- Minimum tank maturity: about 3 months
Care and placement
Zoanthids tolerate a range of lighting spectrums and intensities; medium light suits this morph. They benefit from moderate flow, since low-flow areas allow detritus and algae films to settle on the polyps. They are peaceful and reef-safe with other corals, fish and invertebrates. As a slower-growing encrusting coral it gradually spreads across the rock.
Feeding
The colony is primarily photosynthetic through its zooxanthellae. Optional target feeding with fine foods such as phytoplankton or zooplankton, roughly twice a week, can support growth, but is not strictly required.
Speckled Krakatoa Zoa: Propagation Guide
Overview
Speckled Krakatoa is a designer Zoanthus morph (family Zoanthidae) with a speckled green skirt around a red, volcano-like center. It is a trade-named color selection of these colonial button polyps rather than a separate species. The polyps of a colony stay connected by a stolon, or coenenchyme mat, and Zoanthus is recognized for producing a large number of color morphs of the same or similar species.
Reproductive Mode
Aquarium propagation is asexual. A colony grows because offspring polyps remain attached to the original by a fleshy stolon, and new polyps bud along the mat across the rock. Hobbyists use this budding to expand a Speckled Krakatoa colony rather than relying on sexual reproduction.
Fragging / Asexual Propagation
- Choose edge polyps and slice the connecting stolon mat with a clean razor blade.
- Trace the cut with coral cutters until the section detaches; a diamond band saw is used for thick rock.
- Soak and dry a plug or rubble, dry the frag base, and apply a small amount of cyanoacrylate glue.
- Press the frag onto the plug, let it cure for a few seconds, and return it to the tank.
- New tissue and polyps confirm the frag has established.
Conditions for Propagation
Zoanthus are hardy and accept lighting from lower to higher levels over roughly an 8 to 12 hour day. Healing frags do best in moderate to higher flow that feeds the polyps and clears waste. Because Speckled Krakatoa grows slowly, the stolon fills a plug only over time.
Palytoxin Safety
Zoanthids can contain palytoxin, one of the most poisonous non-protein substances known. Wear gloves and eye protection during fragging, avoid touching your face, and wash up afterward. Never boil, heat, or scrape the rock, since heat can aerosolize the toxin for inhalation. There is no antidote; only the symptoms can be treated.
Common Challenges
Cut polyps may stay closed for several days while healing; stable parameters and gentle flow aid recovery. Speckled Krakatoa is slow growing, so colonies expand only gradually and demand patience. The speckled green and red coloration varies with lighting and water quality, and the foremost hazard is palytoxin exposure.