Earth Day 2010: Coral Propagation and Captive Breeding by Keith MacNeil, MarineDepot.com Reef Squad
That was the first thing that sprang to mind when I was asked to "think green" for this week's article.
On second thought, with Earth Day just around the corner (April 22), advocating ways to lessen our impact on wild reefs—and the environment in general—seemed like more timely, appropriate subject matter.
But how do we apply this "thinking green" concept to our beloved hobby? For starters, we can recycle.
Metal halide bulbs contain 5-7 times the amount of mercury of a fluorescent bulb. When you toss your old aquarium light bulbs into the trash, they will likely end up in a landfill somewhere eventually seeping into our groundwater supply. Not good. Work with your local fish club to gather old bulbs for recycling. Many cities have recycling centers that accept old light bulbs.
You've no doubt heard the adage, "one man's trash is another man's treasure." Next time you upgrade or replace aquarium supplies, consider selling or donating your old equipment. Aquarium-related forums/message boards, craigslist and eBay are a few online sources you might consider posting old aquarium parts for sale or trade. Donating them to a local school science department is another possibility. Repurposing old supplies to create quarantine tanks, refugiums and mixing containers can make for a great weekend project.
Recycling is not limited to aquarium equipment.
You can also "recycle" corals by propagating/fragmenting and sharing, trading or selling the "frags." Coral propagation lessens our hobby's impact on wild ocean reefs. The more propagated corals we have in our tanks the less we'll have to collect from the world's oceans (read Top 10 Reasons to Frag Your Corals).
The best part is you don't have to be an expert aquarist to propagate corals.
We're going to show you how easy it is to fragment corals. We'll start with a green finger leather coral (Sinularia sp.), move on to a branching hammer coral (Euphyllia sp.) and conclude with Acropora (pink milli).
Keep in mind before we dive in that there are different ways to frag and mount corals. The steps below work for us but are by no means all-inclusive.
Propagating Leather "Finger" Corals
These are a great coral for beginners in both propagating as well as for beginners in the hobby. They are hardy, don't require high intensity lighting (but will do fine if acclimated to it) and are fairly tolerant to different water parameters.
The tools needed for this include a razor blade/scalpel or sharp pair of scissors, rubber bands and some pieces of live rock rubble. I also like to have a small container of tank water for rinsing the coral in. I will keep this water container on hand for all types of coral I am fragging, but will refresh the water between corals.
Once you have all your tools in place, take the coral out of your tank and lay it on the table you are going to use. I generally will put the coral on a plastic bag to help keep it moist and to avoid direct contact with the table. Find a nice "branch" that will be easy to remove without damaging other areas of the coral. Don't try to remove part of the middle of the coral; try to find a branch on the outer part of the coral.
With your scalpel/razor or sharp scissor, cut off the section you have chosen.
Dip the original piece of coral in the water set you've set aside and put it back into the display tank. It will be fairly normal for the coral to stay retracted for a few hours to even a few days after it has been fragged. It may even "slime" up.
Now attach the new frag to a piece of live rock rubble. Find a little hole or notch in the piece of rubble for the frag to sit in. Wrap the rubber band around the rock and coral to help keep it in place.
You can put your new frag in your display or frag tank. Don't put it in an area of high flow until it attaches itself to the rock. This will usually take around 1-2 weeks to happen. Don't worry about trying to use glue to hold the coral to the rock. Leather coral slime up too much for any type of glue to work effectively.
I held on to this particular frag (the one I created for this article) for close to a year before trading it for another coral. It grew another 3" by then. It fully attached to the piece of rock within 2 weeks.
Propagating Branching LPS Corals
Frogspawn, torch, hammer, candy cane, etc.
These are among the easiest corals to frag.
Each head has its own skeleton. It is just a matter of cutting the head off below the living tissue of the coral skeleton. Depending on the thickness of the skeleton, you may snap off a piece, use coral shears/cutters/clippers, a saw or Dremel to cut through the skeleton. For thicker skeletons, like the hammer coral in this demonstration, I prefer a Dremel with a diamond bit cutting tool. I personally shy away from the snapping method as it can sometimes damage coral polyps.
Tools used in this demonstration
- Dremel with cutting tool (coral shears will work fine if you don't have a dremel)
- Protective eyewear (if using a dremel)
- Live Rock rubble
- Two-part epoxy for mounting (optional)
Set your tools on a table. Swish water toward the coral so the polyps close. You can use your hand or direct a powerhead toward it. Don't lift the coral out of the tank with the polyps fully extended because doing so can tear coral polyp flesh.
Put on your protective eyewear and bring the coral to the table. Keep the blade and dremel away from the living tissue of the skeleton (and your fingers!).
Avoid cutting all the way through with your dremel so that the new frag doesn't fall to the table. Leave a little skeleton behind and use your hand to apply pressure so it will safely separate.
With your frag safely separated, place the mother colony back into your display tank. Set the fragmented piece in the water you've set aside.
Begin kneading the two-part epoxy to ready it for mounting the new frag. Apply it first to the live rock rubble to secure it and push the skeleton part of your frag into the epoxy. Mold the epoxy on to the skeleton to create a secure hold. I like to carve out a little hole in the epoxy to put the frag skeleton in. You can dab some reef glue for an even stronger hold.
Your frag is ready to return to your aquarium. The epoxy will form a solid bond within 24 hours. Be sure in the meantime not to place the frag in a high flow, high traffic area where it can be knocked over.
It is now ready to go back into the tank and the epoxy should have a good hold of the live rock and frag within 24 hours, so again make sure it is not put in an area of high flow that could knock it over.
Fragging SPS Corals
Acropora and Montipora
SPS corals are ideal for fragging because their skeleton can easily be cut using coral shears/cutters/clippers or a dremel. Some branches may be thin enough to just apply pressure with your fingers to snap them free. Of course, snapping can cause collateral damage so it may not be your first choice for fragmentation.
Tools used in this demonstration
- Coral shears or dremel with cutting wheel (diamond works best)
- Protective eyewear (if using a dremel)
- Coral mounts
- A few paper towels
Once your work station is setup and ready to rock and roll, bring over the coral you intend to frag.
Cut a 1-2" piece of the coral skeleton using your shears or dremel. If the coral colony is large enough, you may make multiple cuts to create several frags. The coral I'm using for this demonstration is on the smaller side so I made a single cut. After you cut away your frag(s), place the mother colony back into your display tank.
You are ready to attach a frag to a coral mount (disc or plug). Some coral mounts must be pre-soaked prior to use. If the mount you are using has been pre-soaking, dab it dry using a paper towel. Add a drop of glue (or more, if necessary) to the coral mount.
Dab the cut end of your coral frag dry using a paper towel. Holding the coral with the cut side up will reduce slime formation. The less slimy the surface the easier it will be to glue.
Position the cut end of the coral into the glue droplet on the coral mount and hold it in place for 10-30 seconds. This is all completed outside of your aquarium.
Place the mounted frag into your aquarium away from high flow, high traffic areas. The coral will be securely glued in an hour. In 2-3 weeks the coral will begin growing on to the mount. I kept this particular frag for almost a year before trading it with a fellow hobbyist. By then the coral had tripled in size and become a mini colony in and of itself.
It took me less than an hour to frag these three corals and that includes taking photographs. Fragging coral does not take long and anyone at any experience level in the hobby can do it. Every propagated coral we put into our tanks is one less coral taken from the ocean. And it can help support your hobby!
Hopefully we've inspired you to try fragging corals on your own. If you have questions, please do not hesitate to let us know.
Captive Fish Breeding
We have come a long way in captive breeding marine fish. But we still have a long way to go.
I had many freshwater aquariums growing up and discovered I could breed most freshwater fish species popular in home aquaria. Sure, some were more difficult than others. But when I switched from fresh to saltwater tanks I learned that fish breeding is much more challenging. I was naïve and hadn't yet researched saltwater fish breeding. I figured I'd have good fortune breeding marine fish like I did with freshwater fish. Unfortunately, I was wrong.
It was not as simple as putting two fish together in a tank and, before you know it, eggs are on a piece of rock. While there are some species that lay eggs in this fashion (clownfish, for example), many others are broadcast spawners with no parental care after the eggs have been fertilized.
The good news is that some of the most popular home aquarium saltwater fish species, including clownfish, gobies, cardinal fish, blennys and dottybacks, have breeding habits that are conducive to captive breeding.
The following links are to websites and books that will help you if you're interested in learning more about breeding marine fish.
- MOFIB (Marine Ornamental Fish and Invert Breeders)
- Clownfish by Joyce D. Wilkerson
- Breeding the Orchid Dottyback, An Aquaist's Journal by Martin A. Moe Jr. One of the first, if not the first, book written about breeding marine fish.
- ORA (Oceans, Reefs and Aquariums). Top breeding facility that provides most of the tank raised clownfish (as well as other fish, corals and clams) seen in the hobby.
While most fish in saltwater aquaria are wild caught, the importance of captive breeding is now beginning to take hold just as coral propagation had not long ago.