Whammin Watermelon Zoa Care Guide

Whammin Watermelon 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.

Overview

Designer zoa with bright pink skirt and green center, evoking watermelon flesh. 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. 'Whammin Watermelon'
• Note: Zoanthus sp. 'Whammin Watermelon' 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 0.5-1 cm per month under good conditions.