How Fast Do Zoanthids Grow?

Learn how fast zoanthids grow, what to do to make them grow faster, and other related questions about their growth rate.

I’ve got into the saltwater aquarium hobby with the intention just to keep a pair of clownfish and several easy to take care corals. I figured it out zoanthids could be a good choice for a beginner like me.

According to my research, these corals were the perfect fit for me; easy to keep, come in different color morphs, and thrive in a different set of conditions.

I’ve decided to start with a small frag of zoanthids and see how they adapt to my saltwater aquarium conditions. To my utter amazement, the zoas began to spread very fast, which made me think what the reason for their fast growth was.

I did some research, and here is what I found.

How fast do zoas grow?

Some types of zoanthids grow and spread faster than others. For example, certain kinds of zoas could grow a couple of polyps in a month, others more than ten. It all depends on the water parameters, tank maturity, lighting, and many other factors. 

In addition, not all systems are the same. Some zoas may grow fast in one aquarium and not grow at all in another.

In general, price is the best indicator of how fast your zoanthids will grow. Some types of zoas grow lighting fast and are on the cheaper spectrum on the price. Others grow very slowly; therefore, they keep a high price on the market. 

How do you make zoanthids grow faster?

Zoanthids are hardy but thrive in a stable environment like any other coral. Keeping the water parameters stable is the first thing to do to make sure your zoas grow faster.

Target feeding is another great way to promote faster zoa growth. Some people claim their zoas spread like crazy when they started to feed them. I have yet to try that method. Feed lightly to avoid nitrate spike in your tank.

Even though zoanthids are considered low-light corals, many people claim their zoas grow faster under stronger lighting.

In general, all zoanthids will grow if they are happy. Just make sure that you provide the right conditions and have patience. Your zoas will grow.

Will zoas grow on sand?

Zoas can grow everywhere, including the sandbed. They won’t grow as fast as on rocks or any other surface, but they will definitely grow.

The problem with growing zoas on a sandbed is that you probably won’t get the best out of them. Their polyps will probably be smaller, the colors won’t be as vibrant as they should be, and if you keep sand sifting fish, there’s a chance your zoas will be closed for most of the time.

Keep your zoanthids on rocks or any other solid surface for the best results. They will grow fast and spread in no time.

What temperature do zoanthids like?

Zoas thrive in water temperatures around 78F (25.5C). I keep my zoas at that temperature, and they seem to do fine. They are colorful, healthy, and have a decent growth rate.

I’ve seen comments on reef forums that some people keep them in higher temperatures without any problem. 

Any water temperature that ranges between 78F and 81F is acceptable. Just make sure that you don’t have large temperature fluctuations in your tank, and your zoas will be fine.

Related: Why do my zoanthids melt| Tips on how to create a zoa garden | What is zoa eating nudibranch | Complete Zoanthid Coral Care

Do zoas like dirty water?

There is an ongoing debate in the reefing community that it seems will last forever. When I first got into the hobby and got interested in zoanthids, I was told that zoas thrive in dirty water and won’t grow in clean tanks. 

However, based on my research and other hobbyist experience, I’ve learned that’s not entirely true. Zoas love rich nutrient systems, but that’s just a small part of keeping zoanthids. You can find thriving zoas in low nutrient and high nutrient waters in the wild.

Sometimes zoanthids are collected from dirtier waters, so naturally, people think they love dirty water. In reality, it means that only zoas can survive in those conditions, and that’s why only zoanthids are found there.

Final Thoughts

Zoanthids have quickly become one of my favorite corals. They are colorful, easy to keep, and grow fast. Some types of zoas grow faster than others, but you get what you paid for in the end.

I would rather have slow growers but beautiful zoas than have a tank populated with unattractive corals. However, what works for me won’t necessarily work for you. Every tank is a different story.

Now, I would like to hear from you. Would you rather keep small frags of high-end zoas and be patient, or would you buy fast-growing zoas from the beginning? Let me know in the comment section.