Filling a tank with corals, especially a large tank, can be very expensive. Most people do not have the money to fill their tank with corals from the beginning (see: Beginner’s Guide to Corals) and choose to add corals slowly over time. However, in the long run you are still putting large amounts of money into ‘filling out’ your reef tank. On top of this, not all the corals you purchase will survive. Every hobbyist is likely to purchase a coral, at some point or another, only to watch it die within a couple of weeks.
It is for this reason that many hobbyists choose to ‘frag’ their corals. Coral fragging is the process of cutting, breaking, or sub-dividing a coral colony to produce multiple coral colonies. This process is possible due to the unique ability of corals to create identical clones of themselves from just about any surviving piece of themselves.
Fragging is Useful in More ways than One
On top of allowing you to reproduce multiple coral colonies, fragging corals allows you to control coral aggression within your aquarium. In the case of particularly aggressive coral species, such as those in the genus Euphyllia, allowing corals to get too close to one another can have potentially disastrous consequences. Fragging large and aggressive corals can limit such aggression.
The Four Stages to Fragging Corals:
Stage 1: Conditioning
It is important to note that only healthy corals should be fragged. This is because damaged or sick corals are less likely to recover from the fragging process and may perish. Ensure that you meet the corals environmental and nutritional needs for at least a few weeks before attempting to frag it. A healthy coral will have extended and inflated polyps.
Stage 2: Planning
The old adage goes, ‘5 minutes of planning saves 5 hours of frustration.’ This is also true when it comes to fragging corals. Make sure that you think about your fragging strategy before you attempt to frag any coral. Identify where you plan on making the cuts and make sure that you have all the necessary equipment ready before removing a coral from the tank. This will ensure that the stress placed on the coral is kept at a minimum. Also, be aware that if you are fragging soft corals or LPS corals, they will look very different once you remove them from the water.
Stage 3: Creating the frag
Creating the frag itself can be done in many ways and is largely dependent upon the species of coral that you plan on fragging. If you are keeping soft corals or LPS corals, then there are several ways of fragging a coral. Fragging doesn’t always involve dividing the coral itself, as is the case with the ‘chipping method’. This is a straightforward technique involving a chisel and a hammer. Select a piece of live rock which has LPS corals attached to it and using the chisel and hammer tap the live rock until it breaks into two or more pieces. This creates multiple coral colonies. This technique can be used with corals such as; Zoanthids, Mushroom Corals and Xenia.
Shearing another technique which you can use to frag soft-bodied coral species such as the Devil’s Hand, Finger Coral, Cabbage Leather and Xenia. You can use a pair of scissors to cleave off a branch or lobe of the coral. The Slicing method is the technique of choice for these harder-to-cut soft coral species. Scissors/shears are fast but cumbersome and some coral species may require the use of a scalpel or razor blade.
If you are keeping Small Polyp Stony Corals (SPS) then the ‘snapping method’ is probably the easiest way of creating coral frags. This technique can also be used with branching varieties of LPS corals which have relatively thin branches. Using wire cutters or bone cutters, squeeze the handle and twist to snap off a branch or plate.
For SPS corals that have branches too thick to snap the only way you are going to be able to get in there and make a frag is to saw through the coral’s skeleton. You can use a band saw to do this. This sounds like a daunting and risky task to most hobbyists, so in all likelihood you will need to gain some confidence fragging other coral species before attempting this technique.
Stage 4: Attachment
After you cut the coral and create the frag, you generally need to attach that fragment to a substrate of some kind. If you make a fragment of a soft coral but don’t attach it to anything, it will float away in your aquarium. Stony coral frags won’t blow away in the current, unless you have some SERIOUS flow in your tank, but your frag will get damaged if it falls to the bottom or gets covered by the sand.
Tools for Attaching
Cyanoacrylate glue – Cyanoacrylate glue (gel) is one of the most popular tools used when fragging corals. Cyanoacrylate glue is commonly sold under the name ‘super glue’. Cyanoacrylate glue is reef-safe and easy to use. Just dab it on a frag or piece of live rock, hold the coral in place for a second or two and give it a few minutes to set. If you can find it, it would be a good idea to buy super glue gel instead of regular super glue. The gel is thicker and much easier to use.
Two-part epoxy – This is an alternative to glue. Two-part epoxy is sold in a tube. When you cut off a portion and knead it with your fingers it creates a chemical reaction that allows the epoxy to set. This can be used to bond a coral to a rock or two pieces of rock together.
Rubber bands – Rubber bands are an alternative to glue and work great for the soft-bodied Leather corals. Leather corals are notoriously difficult to glue into place. Their slime coat protects them from the glue and they often slip away from the grasp of the sticky glue. Rubber bands are sometimes effective at holding slimy coral frags in place.
You can either attached a coral frag to a piece of live rock or to a frag plug. The only downside to using live rock pieces is that the shape can be irregular, which can lead to falling frags if not properly bonded into place. On the other hand, frag plugs are specifically designed for attaching coral frags to.
When fragging corals safety should always be your top priority. Some coral species are known to release a harmful chemical called palytoxin. It is harmful if it comes into contact with your skin, so wearing gloves is highly advisable. By the same token, safety goggles are highly advisable. If you wear prescription glasses, then there is no need to wear goggles.