Fragging Zoas

Zoas are a very common type of coral found in many home reef aquariums. They come in a wide variety of color combinations that make them appealing to many people. Here we will show step by step how to frag some zoas that have overgrown a large frag plug.

An ovegrown frag on the top

Today we will use these Gobstopper zoas to show how to frag. Normally a nice frag plug like this will find a spot in my tank and allowed to grow out from here. However, for the purpose of education we will remove a few polyps and put onto a new frag plug.

Equipment Needed

Starting with our protective gear of course, we need gloves and something to cover our eyes. I like to use food grade gloves that I buy from Costco and have this simple eye protection that can be found at most hardware stores. It is thought that some zoas can create the palytoxin and to avoid any possible dangers we use our gloves and eye wear the entire time we handle the zoas.

Next are the tools we will use to actually cut the corals. In the past I have used an exacto blade with tweezers but have had much better results since I have switched over to wood carving tools. They are small, sharp enough, and allow me to dig into the rock under the polyp easily rather than pull the polyp with tweezers. You can buy a pack on Amazon for rather cheap too, which is a nice bonus!

My wood carving chisels

You will want a small container or a towel to help contain or catch the water that drips off the frag. We won’t be using a chisel with a hammer today so a shallow bowl will even work. I am using one of those drawer organizing tubs that you would put pens or office supplies in. It’s small, holds water, and I had it on hand already! I am also using an old container that held soup at one point to hold the frag in water.

Last we need something to glue the polyps too, either a frag plug or a piece of rubble rock, and some glue. The glue needs to contain Cyanoacrylate. This is a compound that cures extremely fast when exposed to water. Gel glue also works better here because of it’s thickness. I have used a wide variety of brands and all work relatively the same. Gorilla Glue with cyanoacrylate is what we will be using today.

Fragging Process

Grab the coral to frag and gently swish it around in the tank water before you remove it. This allows the polyps to close up fully and protects the coral a little bit. Then take it over to your fragging table.

We are going to start by finding the areas on the edge easiest to cut. This overgrown frag plug makes it easy to show.

After finding our polyp we want to remove, start by cutting around the polyp first. Zoas create a mat that connects each polyp and we have to cut that first. I have shown here in this picture where I will make the cuts at with my carving chisel.

Red lines show where I will cut around a polyp

Now that the mat is cut around the polyp, we want to take our chisel and slowly start to dig under the polyp. We want to dig into the rock or the frag plug and, ideally, would remove a small piece of the rock under. The goal here is to remove the polyp without splitting the base. This can take some experience to get good at so don’t fret if your first few polyps get split in the process.

Tweezers point to two polyps I fragged

If you do split a polyp still treat it like it’s a whole piece. When I used tweezers to pull polyps off I was always splitting the base of the zoas. I had a decent survival rate. Around 4 out of 5 polyps, or 80%, would live. Since I switched methods to the wood carving chisel I have yet to lose a polyp!

Now that we have cut our polyp off, we apply a little glue to the surface of our rock or plug. Make sure the surface is dry so that the glue can get a good hold on it. Next inset the polyp base into the glue. Eventually the polyp will grow a new mat that will spread over the top of the glue.

Two dots of glue on the plug

Before you stick your new frag into a tank with flow, grab a cup and scoop up a little tank water. I have this solo cup I use for just this purpose. Place your new frag gently into the cup and let it be for around a minute. This gives the glue time to harden up before we expose it to flow. I have ruined frags by putting them straight into flow which knocks the polyp over on its side, gluing the actual polyp down. This keeps it from opening or closing fully and caused some unintentional deaths.

New frag next to the older frag

Now that it’s cured for a moment you can place it either into your frag tank or display tank! Some people like to use dips, such as iodine, after fragging to prevent any infections. I have not used an iodine dip, or any post frag dip for that matter, and haven’t had an issue with infection. I am careful to put the new frag into water as soon as I can and I think that helps the recovering time.

The mother coral should open back up really fast after being put into water. The new frags, depending on how we did with the process, can take up to a few days. When I split the base of the zoa sometimes it can take a week before it opens again. Now that I chisel underneath the polyp they usually open up as fast at the mother colony; within an hour.

That’s it! A simple process to spread your zoas out around your tank or to trade with friends. If you have questions or comments be sure to share them!


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