Coral propagation refers to the reproduction of coral and is often accomplished by marine aquarists through a process called fragmentation or, as it is commonly called, “fragging.”
Fragging coral is remarkably simple and is an activity in which many reef aquarists become involved. Fragging allows people to share “frags” of their corals with friends and other aquarists, while keeping the “mother colony.”
In terms of conservation, coral fragging, whether done by the amateur aquarist or the commercial coral farmer, promotes a sustainable hobby in which every wild collected coral can be “fragged” to produce many offspring. This sort of conservation through propagation is very popular amongst conservation-minded aquarists.
Corals are generally fragged out of the water, which should not pose a problem so long as the coral is returned to the water within 15 minutes and the air temperature is in the mid-70s Fahrenheit and not too dry (a humid environment is best). If you are fragging a coral with large polyps, gently wave your hand over the coral before removing it from the water so that the polyps retract. Major tissue damage can occur if you lift some corals with large polyps out of the water while the polyps are fully extended.
Use Coral Cutters or a Coral Scalpel
To propagate a coral by way of fragmentation, remove the coral to be fragged from the water and, using a pair of coral cutters (for stony corals) or a coral scalpel (for soft and leather corals), remove a piece of coral from the mother colony. Gently handling the coral should pose no significant damage to the polyps, but it is best to use gloves to protect yourself and the coral while fragging.
Glue or Epoxy
Once you have removed the frag from the mother colony, you can return the mother colony to the water. Using the gel-type Crazy Glue (or Super Glue) for SPS corals and epoxy for LPS, affix the frag to a rock or plug and return it to the water. In time, the frag will encrust the plug or rock.
The reason to use epoxy on most LPS corals is the fact that epoxy can handle the weight of the frag better, and it generally only comes in contact with the dead calcareous skeleton. The epoxy curing process will kill any tissue it comes into contact with, so Crazy Glue is really the best bet for SPS corals.
Tips and Tricks
It is important to never frag more than about 25-30% of a mother colony at one time.
Robert Weber of Mistress Corals, adds that he has found waiting three to four days after fragging from the broodstock colony before mounting the new frag increased the survival rate, color, and growth.
It is best to dip both the mother colony and the new frag in a coral dip such as SeaChem Reef Dip or Two Little Fishies ReVive Coral Cleaner after fragging. This dip will help ward off bacteria, fungus, and protozoans. Some aquarists also use a vitamin C additive such as Kent Marine’s Marine C following propagation to aid in healing.