How to Get Zoanthids to Open

Zoanthids open by extending their tentacles.

Zoanthids, or zoas, are saltwater corals that exhibit a wide range of colors. Many hobbyists are collecting zoas in their salt-water tanks, as they are hardy creatures that easily adapt to their surroundings. Zoas have tentacles that extend, which refers to the opening of the zoa. For zoas to open and display beautiful colors, they must well-cared for.

Instructions

1. Submerse zoanthids in a reef tank of saltwater with a temperature 74 to 80 degrees Fahrenheit. Keep zoas stored separately from other aquarium-based organisms for about 10 days to make sure they don't have diseases. Keeping zoas in a tank under the correct conditions will help them open.

2. Employ metal halide or t-5 marine lighting in the aquarium tank to get the best results from zoas, but keep them in the shaded areas of the tank, as they require only minimum lighting.

3. Monitor the zoas for about five days. If the color starts to fade, the zoas may be exposed to too much light or are not receiving enough light to produce nutrients for themselves or their hosts through photosynthesis. Try moving the zoas away from the light or closer to it, depending on how close it is, and monitor the color for a few days. If the color starts to improve, the zoas should open in time.

4. Place zoas near the water pump in the aquarium so the pump can filter the nutrients absorbed by zoas. Zoas thrive best when they are placed on rocks, aquarium glass or other hard surfaces. The water flow in the tank should be moderate to encourage the zoanthids to thrive and open.

5. Handle zoas with care. Refrain from putting your hand in the tank if you have any cuts or wounds. This is extremely dangerous, as some varieties of zoas contain a toxin called Palytoxin, which can be harmful to humans. Wear gloves when handling zoanthids.

References

• Easy Reefer: Zoanthids
• Reef Chronicle: Coral Polyps
• Nano-Reef: Corals
• Blue Zoo Aquatics: Handling Zoanthids