Zoanthid corals are some of the most popular, colorful, and hardiest corals you can collect for your saltwater tank. Zoanthids are also referred to as Zoas, Zoos, or button polyps. Zoanthid corals are found in many colors and are quite simply a beautiful addition to your tank. The Zoanthid coral attracts both new and experienced aquarium reef keepers. The ease of Zoanthid coral care is a huge bonus to newbies and the bright beautiful colors keep the experienced reef keepers coming back for more.
Common Names: Zoanthid Coral , Zoa, or Zoo
Skill Level: Beginer
Light Level: Moderate to High
Water Flow: Moderate
Water Conditions: 72-78° F, dKH 8-12, pH 8.1-8.4, sg 1.023-1.025
Zoanthids are fairly easy to care for and are much more tolerant of tanks which are struggling with nitrates and phosphates (dirtier water). If you search the internet I see many places where people suggest keeping the corals in tanks “dirtier” for the best coral growth and health. I strongly disagree. While Zoas can survive in these conditions it’s not favorable. As a reef tank owner for many years I have had tanks which have struggled with high nitrates and phosphates but never have I noticed where coral health or growth is improved by living in dirty water. I believe the idea behind a healthy coral in dirty water is that people think the corals can absorb more nutrients in dirtier water. My experience points to keep your water as clean as you can through proper filtering and water changes, then just feed your corals. Corals do eat, they grow faster when fed, so feed them for maximum health and growth. Just do your best to keep the water clean. I have read many suggestions on what to feed you’re Zoanthids but the only for sure food I have seen mine accept is Cyclopeeze with a turkey baster, so that’s what I would recommend for food. On the flip side, you don’t have to try to try to feed the corals directly. Under Moderate light and flow they will grow just fine by filter feeding on stray fish food and other organics in your tank.
There is a very broad range of Zoa colors available to the reef keeping hobbyist including red, green, pink, orange and blue. For the longest time the blue Zoas were the most uncommon to have, however in the last year or so they have become much more common. It seems like now the Zoanthids commanding the highest price tag are the ones with the coolest name. Darth Maul Zoas and Fruit Loop Zoas would be a good example of this. I have to admit I am pretty horrible when it comes to keeping track of all the new fancy names and when I talk with people about Zoas I usually just go by color descriptions. Picture below is an example of a darth maul polyp.
Zoanthids can also grow together without fighting, thus offering an array of color arrangements. Zoanthids are tube like and come in multiple sizes. If you picture a full grown RBTA and shrink it, this is what a Zoa body resembles; in fact Zoanthids are often referred to as colonial anemones. These colonies can quickly cover a rock completely. While I have never seen any sign of different Zoanthid color strains fighting, I have seen where one type will grow much faster than another and eventually over take one another. Image below shows two different kinds of Zoanthids living together on the same rock, unforunantly at some point one of these will overwhelm the other.
Moderate to high lighting with moderate flow will keep your Zoas happy. In fact under T5’s , 400W halides, and now LEDS I have not found a light range in which they were unhappy. Place them in a flow where you can see the polyps being slightly moved around. Too little flow and they will start to suffer, too much flow and the polyps will not be able to fully extend.
The physical action of Zoanthid fragging is a major pain. It is possible and I have done it many times, but it is very time consuming and honestly it’s dangerous. To manually frag a Zoanthid I prefer to take a small scalpel or razor and cut the Zoa as low on the stalk as possible. The polyps are very slippery so be careful not to lose it. I then take the newly cut Zoa and place it onto a frag plug which has had a drop of superglue already starting to dry on it. The wet polyp will quickly adhere to the superglue. This is difficult in that you don’t want the polyp to touch the super glue only the stalk. Between cutting the Zoanthid and gluing them onto the frag its very time consuming. I prefer to let a large colony build and spread over a rock or rock rubble then just bust the rock apart. This is so much easier.
In the above paragraph I mentioned that fragging a Zoanthid can be dangerous. It’s extremely important to be aware that Zoanthids can be toxic to humans, in particular Palythoas. Always wear gloves, eye protection, and keep your mouth closed when handling or if your hands and/or arms are in the tank. Remember to wash your hands thoroughly after you have finished handling or after being in the tank. Until I knew better and actually saw someone get sick from handling Zoanthids I never took it serious enough. I watched a fellow reefer frag a Zoa colony for a friend without gloves or eye gear. After the fragging process was finished he rubbed his eye. Literally the whole side of his face for the rest of the afternoon was swollen and he complained of numbness. He never made the trip to the emergency room but it took a full two days before his face was back to normal. If it were me I would of went to the hospital just in case.
Overall Zoas are a beautiful addition to a reef aquarium. If you search online for Zoa garden or Zoanthid gardens you can see some very beautiful tanks showing off just about every color imaginable. If you’re going to own these corals though, just be careful what you touch.