Growing live corals is a rewarding experience, but it can be intimidating to get started. If you’re interested in cultivating a reef of your own, you’ll need to know the basics of the aquaculture practice known as fragmentation, or “fragging.” Most individuals find that fragging is a simpler process than they initially imagined, and here, we share tips on how to get started with coral propagation.

What is Fragging?

Fragging refers to the process of removing a small segment from a “mother colony” of coral. Traditional fragging generally consists of taking fragments of at least three square centimeters, while micro-fragging involves removing a section of no more than one square centimeter. Fragging is a sustainable practice, and allows for both the preservation of the mother colony and impressive tissue growth in new colonies. If you’d like to get started with this practice, here’s what you need to know:

Tools for the Job

Successful coral propagation through fragging is made easier with some common tools, including:

  • Razor blade, scalpel or other fine-edged cutting tool
  • Stainless steel scissors or wire cutters
  • Screwdriver or chisel

For more advanced or larger projects, more significant equipment will come in handy, such as:

  • Bone cutters
  • Rotary tool
  • Band saw

Safety Materials

During the fragging process, some corals may emit the chemical palytoxin. This substance is harmful if it comes into contact with your skin, so you’ll need to have the following safety materials on hand:

  • Rubber gloves
  • Safety goggles

Additional Materials

  • Cyanoacrylate glue(aka super glue) – There are any number of hobby-specific brands (SeaChem Reef Glue, Two Little Fishies CorAffix) but they are the same substance used in more typical products like CrazyGlue. Gel formulations are the easiest to work with.
  • Coral dip such as SeaChem Reef Dip or Brightwell Aquatics MediCoral – these brands are easy to work with and fairly safe for beginners. For those with a bit of practice (or gray hair) the old-school Lugol’s iodine solution is tough to beat

Marine epoxy putty, e.g. Instant Ocean Holdfast or Two Little Fishies Aquastik  – these putties are similar in texture to clay, and start to set after they are smashed up to mix the two ingredients together. In the last few years, they have become available in a wide variety of colors, which is convenient. One thing to keep in mind about marine epoxy – it is not an adhesive – it does not stick two surfaces together the way glues do. It can be formed to take the shape of a surface, and then it hardens.  It is good for rock work, or to form spaces for placing corals, but its strength comes from the mechanical connection – forming around shapes on the surfaces. Marine epoxy is not an adhesive.

How to Get Started

Once you have your tools and safety materials, it’s time to move on to the exciting part. There are several different fragging techniques, and we’ll outline a few of the most common options here.

When you’re ready to begin, you’ll need to prepare a suitable environment for fragging. Corals will need to be removed from water to be properly fragged, so the room should be kept in the mid-70s Fahrenheit. If possible, create a humid environment, as this will yield best results. If you’re working with coral that has large polyps, be sure to wave your hand over them to create some water movement before removing. The polyps will recede by expelling some water, which reduces strain on the coral polyps when they lose the support of the surrounding water. Tissue damage will likely occur if the coral is removed with extended polyps. The fragging process should only take a few minutes, and you should aim to return the mother colony to its original location within 15 minutes of the procedure.

To create the fragments, you can choose from the following removal methods:

  • The chipping method. This technique is simple, and involves using a chisel or screw driver, and perhaps a tap hammer to remove fragments from the mother colony. This method works best with encrusting corals.
  • The snapping method. To perform the snapping method, use wire or bone cutters to snap off a fragment of the branch or plate. This technique is most successful with branching small polyp stony corals, but is also effective in large polyp stonies with a distinct branching structure like Euphyllia or Caulastraea
  • The shearing method. This practice is best for soft-bodied species, and involves using scissors to separate fragments from the lobes or branches. The slicing method. Scissors will work for this technique, but a scalpel or razor blade is the best tool for the job. This technique is ideal for soft species like Nepthea, which are difficult to cut with scissors.
  • The sawing method. Sawing is often most effective for stony corals with thick branches or massive growth forms like Montastraea or Goniopora. This method is the most difficult to achieve and requires a high level of precision.

When fragging corals, it is best to cut or break the skeleton first, then use a razor or other sharp tool to cut the coral flesh. This provides a cleaner cut, reducing the opportunity for microorganisms to attack the coral flesh. Ragged edges are more susceptible to infection/infestation than a clean cut. Once you’ve collected the fragments using one or more of the techniques outlined above, you’re ready to attach them to a substrate. There are several attachment methods to choose from, including:

  • The glue method. Many beginner reef enthusiasts will find that the glue method is simplest to work with. Simply place a small amount of super glue or similar adhesive to the frag plug or live rock, then press the frag onto the substrate for about 30 seconds until fully secured. When using this method, be sure that both the frag and the substrate to which it will be attached are dry. If you’re using super glue without removing pieces from the water, it’ll be helpful to use some type of physical holding or grasping. For example, stick the end of the coral into a crevice of the rock work to ensure a stronger bond.
  • The rubber band method. Securing the frags with rubber bands is an excellent solution for leathery species that produce slime. For best results, try to select an irregularly shaped live rock and place the frag in a depression of the surface area. Then, use a rubber band to adhere the pieces. Soft corals like Sarcophyton are great candidates, and can be skewered with a toothpick or similar to provide something to wrap the rubber band around.
  • The slow creep method. This technique is ideal for encrusting coral species. To get started, take a frag plug and insert it at the base of the encrusting coral. In just a few days, you should notice that the coral will begin to grow over the obstacle. Instead of breaking a piece from the colony, a plug or other substrate is placed next to the coral. Then, the coral is allowed to grow onto the plug, and the plug can be removed from the colony.

Coral propagation through fragging provides a great opportunity for reef keepers to experiment with coral reproduction. If you’re interested in pursuing this aquaculture method, you’ll need to have the right set of tools on hand. Livestock can only thrive under ideal conditions, so be sure that your aquarium lighting system is up to the task. When you’re on the search for a product that’s adaptable and durable, browse our two generations of reef lighting systems. Both are excellent options for reef keepers of all experience levels and are backed with a three-year warranty. To learn more about our cutting-edge reef lighting systems and accessories, please visit us online.