Propagating Soft Corals

Introduction

Before we begin, let us first start by saying that you do not need to be a Marine Biologist or Rocket Scientist to propagate most soft corals. Taking cuttings from these types of corals is extremely easy and we at Reefs UK encourage as many people to do this as possible. For those of you who have not heard of Reefs UK, we are an organisation who promote the use of captive breeding and coral propagation within the marine aquarium trade.
The following information is based on Reefs UKs own experiences on making cuttings of soft corals and we have tried to write it in such a way that for anyone who has never propagated soft corals before, they can read this and get started immediately. We will apologise now to those of you who have been doing this for years, as we will probably be going over old ground. As a note, when Soft-Branched corals are mentioned, Cladiella, Alcyonium and Nephthea are included in these corals. When Leather corals are mentioned, they include Sarcophyton, Sinularia and Lobophytum.

Water Quality

We have listed what we consider the water quality should be before taking a cutting but we really do not want to get into the conversation on what levels the water quality should be as this seems to be a subject of its own. What we will say is that obviously there should not be any traces of Ammonia, Nitrite and Nitrate. In addition, Alkalinity, pH and Calcium levels should also be at the commonly recommended levels. Obviously for anyone keeping a reef tank then this should not be problem, however it is worth testing your water before taking a cutting just in case something is not at its normal level. By doing this, it will help the new cutting establish itself without having to fight against toxic/semi toxic traces.

• Temp = 78f - 80f
• S.G = 1.023 - 1.025
• pH = 8.1 - 8.3
• Ammonia = 0mg/L
• Nitrite = 0mg/L
• Nitrate = less than 1ppm
• Calcium = 390ppm - 420ppm
• Alkalinity = 2.8mg/L
• Phosphates = 0ppm
• Silicates = 0ppm

Rock Attachment

Obviously, you will need something to attach the cutting to once you have made the cut from the main coral, otherwise it will just float around in your tank forever and a day. We recommend the use of small pieces of ocean rock about 1" to 2" square for this. We have also used pieces of coral stone and believe that these corals will grow onto any reef safe object if attached correctly. The cutting will normally take about one and a half weeks to attach to the rock so you will need something to hold it in place in the meantime. Rubber bands seem to be the easiest to use for Soft-Branched corals.
At this stage, put the rubber band around the rock but ensure that there is enough give between the band and the rock to hold the cutting securely. For Leather corals, place the rubber band tightly around the rock, as you will not be using this to hold the coral directly. It is quite hard to get the rubber band to apply the right amount of pressure without splitting Soft-Branched corals into two. Either that or it is too loose and the water flow eventually forces the cutting to escape from the rock. A little practice and you will soon learn how loose the rubber band can be.

Cutters And Other Accessories

It appears the best way to take cuttings is to use a sharp scalpel as this will ensure that you slice the coral quickly and cleanly. This solution is fine for Leather corals but we have had no joy using scalpels to cut Soft-Branched corals. What we found was, because the coral is so soft, the coral branches just move away when you apply any type of pressure to them. Trying to hold one end of a branch with one hand while using the other to make the cut does not work at all and it applies unnecessary stress to the coral. For Soft-Branched corals, we use a very sharp pair of scissors. Other accessories you will need are a small glass bowl filled with some of your aquarium water and a toothpick, which is required for attaching Leather corals to the rock. At this stage, fill the bowl with aquarium water and place the rock with the rubber band attached to it, into the bowl.

Before You Cut The Coral

Now that you have tested the water quality and prepared the rock that will hold the cutting, all that is left to do is make a cut. Now this is were you start to have doubts but at the end of the day, it is the only way you will propagate your coral. Before considering taking a cutting of any coral, ensure that the coral is in good health. If for some reason the polyps have remained closed that day, put off cutting the coral for a few days to ensure everything is OK. As soon as you take a cutting from the desired coral, the cutting and the coral will close up and shrink down in size. Do not be alarmed as this is quite normal and is to be expected.

Cutting Soft-Branched Corals

Select a small branch that has 2 or 3 other small branches growing from it. It does not matter how big the branch is that you choose but we always choose one that is about 2" to 3" in length. This will allow you to take plenty of other cuttings in future without hacking the coral to pieces. In addition, the cutting will grow quickly so that the 2"cutting will soon be 6" to 8" in a few weeks time. Place the open scissors around the branch you have selected aligning them about half inch from where that branch is growing from the main coral. Quickly and precisely, cut the coral with the scissors. You want to ensure it only takes one attempt to cut the coral as this will guarantee you have a clean cut. The main coral will probably curl up into a ball, similar to how it does at night. Generally it will only take a few hours for the main coral to open again. You will notice some mucus being excreted out of the base of the cutting and also where the cut was made on the main coral. Do not worry as this is quite normal. Remove the cutting from main tank and put it into the bowl of aquarium water. Do not worry about exposing the coral to air, as this brief encounter will not harm the coral.

Cutting Leather Corals

If the Leather is a Finger Leather coral, you can also use the same method as described in the section "Cutting Soft Branched Corals". As mentioned already, we suggest cutting a small section of the coral. Again, after you have made the cut, remove the cutting and place it in the bowl of aquarium water. Cutting things like Mushroom Leathers (Sarcophyton sp.) are a little more tricky. Some times, you could be lucky as some leathers literally rip themselves apart. This is quite common and is considered as a form of asexual reproduction.
To cut the leather, slice a small cut from the top centre of the coral out to the edge. Then do the same but leave a 1" gap from the last cut. Image a round cake and you wish to cut a slice for yourself. That is exactly the way you cut the coral but do not cut all the way through the coral. What you want is for the coral to slowly split apart. This may take several days or even weeks and you may need to assist with a deeper cut along your original cut. Make sure you leave plenty of time for the coral to recover before making another cut. Once most of the cutting has split away from the main coral, make the last cut to completely detach it. Remove the cutting and place it in the bowl of aquarium water.

Attaching Soft-Branched Corals

As mentioned before, the coral cuttings will need something to attach to so this is where the small 1" square rock, and the rubber band comes in. Take the cutting from the bowl and ease about a quarter to half of an inch of the cuttings base through the rubber band. Doing this while keeping the cutting out of the water may help as you should find the coral less slippery to work with. Try not to apply too much pressure to the cuttings base, as this will cause even more stress to the coral. Also, if you are having trouble sliding the cutting under the rubber band, keep dipping the cutting in the bowl of water so it is kept moist. Once the cutting is securely attached to the rock and you have checked the rubber band is not too tight, place the cutting back into your main tank.

Attaching Leather Corals

When attaching Leather corals, you will still need the 1" square rock but unlike the Soft-Branched corals you will not be using the rubber band directly to attach the coral. Instead take the coral from the bowl and push a toothpick through the centre of the cutting so about a quarter of the toothpick is still showing from the top. Push the base of the toothpick between the rock and the rubber band so the base of the cutting is firmly touching the rock. Once the cutting is securely attached to the rock, place the cutting back into your main tank.

Cutting Placement

When the cutting is back in the main tank, place it on the bottom of the tank directly below the lighting and in good water flow. We have found that placing these cuttings in the direct path of a pump prevents them from opening. If the pump is at one end of the tank, try placing the cutting half to three quarters way up the tank. This provides enough flow to stimulate the cutting and remove any outer skin it may decide to shed. The cutting should start to open within 4 hours (approx.). Within 24 hours, both the main coral and the cutting should look as though nothing has ever happened to them. One more thing to watch out for, do not place the rock near another rock in your tank, as the cutting will also grow onto that rock as well.

Soft-Branched Coral Growth

We recommend leaving the cutting alone for one and a half weeks before checking if it has grown onto the rock. These cuttings generally attach within one week. If left much longer, the Soft-Branched corals will start to grow onto the rubber band. To remove the rubber band, pick up the rock with the cutting attached and slowly ease the rubber band from the coral. Be careful not to pull the rubber band too quickly as it will pull the cutting from the rock. As you lift the band, you should be able to see the cutting has grown onto the rock. Completely remove the band but do so very carefully as although the cutting will have attached, it has only just started to grow onto the rock and will require a few more weeks before fully attaching itself.

Leather Coral Growth

We find most Leather corals attach in 2-5 days but leave about one week before removing the tooth pick so you do not disturb the cutting. To remove the toothpick, pick up the rock with the cutting attached and slowly ease the toothpick back out of the cutting the opposite way it went in. Again, as with the Soft-Branched corals, be very careful not to pull the cutting away from its rock. Once the toothpick is removed, remove the rubber band from the rock.

Final Stage

When placing the coral back in the main take, position the cutting a little further away from the pump just to make sure the flow does not pull the cutting from the rock. Leave the cutting undisturbed for another three to four weeks before moving them from your tank. This will give them plenty of time to establish themselves. You should see quite a bit of growth from the cutting in the first few weeks.

By Reefs UK