ECC Alien Eye Zoanthid

Zoanthids Care Guide

Zoanthids (Zoas) are a popular choice in reef tanks for good reason. They add strong color, work well in almost any aquascape, and are beginner friendly. Each frag is made up of individual polyps that open during the day and, over time, can spread across nearby rockwork to form an impressive colony.

Because Zoanthids grow out over rockwork rather than upward, it is important to think about the space around the frag. Many reefers choose to create a dedicated rock island for multiple Zoanthid varieties, creating what is commonly known in the hobby as a Zoa garden.

Water Parameters

Corals thrive in stable water conditions with regular water changes. Routine water testing helps ensure these needs are consistently met.

• Specific Gravity (Salinity): 1.025-1.026
• Temperature: 75-78 Degrees F
• pH: 8.1-8.4
• Alkalinity: 8-9.5 dKH
• Calcium: 400-450ppm
• Magnesium: 1300-1450ppm
• Nitrate (NO3): 10-25ppm
• Phosphate: 0.01-0.1ppm
• Nitrite (NO2): Undetectable
• Ammonia (NH3): Undetectable

Lighting Requirements

Zoanthids usually do best in low to moderate lighting, around 75-250 PAR, however they can adapt to various light intensities. High light may enhance color vibrancy for certain varieties, but intense lighting without proper acclimation can lead to bleaching.

For those with mixed reef tanks, a PAR meter is invaluable for fine-tuning light levels across different corals, helping ensure each coral gets the right intensity for its needs. This careful setup supports the coral’s vibrant color and long-term health.

Ideal Tank Placement

Place Zoas in mid-to-lower tank regions or shaded spots initially to gauge their light preference, moving them higher if needed. Experiment with locations in the tank where water flow is gentle but keeps the polyps open and free from debris. 

Water Flow Requirements

Zoanthids prefer a moderate, steady flow to keep detritus from accumulating on their polyps. Too much flow may cause them to close. If polyps remain closed, try adjusting their placement to slightly less intense light or different flow levels.

Aggressiveness and Compatibility

Give Zoanthids a little room to grow. Some types of Zoanthids grow faster than others and can quickly start encroaching on surrounding corals.

Feeding and Nutrition

Primarily photosynthetic, Zoas can thrive on light alone, though occasional feedings with coral foods such as Reef Chili and amino acids like CoralAmino can enhance growth and coloration.

Growth Rate and Pattern

Zoanthids grow relatively quickly. If you don't want the zoanthids taking over your rockwork, try placing them on their own rock island to contain their growth to an area that's easy to keep at bay.

Acclimation Process

Acclimation is essential for corals to adjust to their new environment. For a full step-by-step process, refer to our Coral Acclimation Guide.