Captive propagation of predatory corals requires that the reef farmer establish a continuous source of food for these types of coral. At GARF we are working on a method that uses a variety of prepared diets. We are working on several other methods of feeding these corals on a diet made up of living algae and zooplankton that we grow here. I enjoy culturing live food for my aquariums and I've developed several ways to make this easy.
At GARF we utilize a method of growing live food that uses hanging plastic bags. The bags that we use are called bag liners in the aquarium trade. These thick plastic bags are approximately 8 in. square. We started using this method called Bag O Bugs several years ago when we were isolating different types of algae and rotifers. Many types of food organisms can be isolated from the live sand that people make using GARF GrungeTM. By filling each of these bags with a quart of fresh Instant ocean water we can culture and isolate different populations of micro invertebrates and algae.
The system for making our Bag O Bugs is set up in the South-facing window that is shaded by large trees. We made this system by attaching 1-in. square boards to the window frames with wood screws. The bags are held in place with plastic thumbtacks. You can also make a rack for your bags using PVC pipe and fittings. This semester we are using natural sunlight, but 40 W fluorescent lights can also be used. This system of propagation allows us to have large numbers of sterile containers that we can inoculate with selected organisms. Often we are looking to isolate a certain Micro algae. After the first bag is populated with a mixed culture we hang up four more bags full of sterile water next to it. We then put one drop of water from the first bag in the next bag. A single drop of water is removed from this bag and put into the bag next it. We repeat this dilution several times.
Feeding the artificial diets to these corals is important because the results can be duplicated in several different parts of the world for research.
| || At GARF we have developed a very simple diet using algae flake food and SeaChem Reef Plus. We make this diet in small quantities and store it in the refrigerator. The flake food is first soaked in Reef Plus by mixing 1 tbsp. of flake food in 3 tbsp. of Reef Plus. We place this mixture in the refrigerator to rehydrate for twenty-four hours. When we are ready to blend this mixture we add 12 ounces of clean Instant Ocean. This mixture is blended for several minutes and is ready to use.
During the last year we have also been using frozen Micro algae that is grown for the aquaculture business. These concentrated algae can cause water quality problems if they are not used carefully. When you are feeding the captive system large amounts of prepared food it is important to have biological filtration and frequent water changes. The system that we are using to produce our cuttings now has both an under gravel filter and a complex biofilter. Both of these filters can be disturbed by stirring the gravel. The detritus released from the sand is a good source of food for the aquarium. In our years of research into reef keeping we have used less and less filtration, but these predatory non-photosynthetic corals will produce more waste products.
The second most important parameter that must be controlled if you are going to produce quantities of non-photosynthetic corals is water flow. Each of the species requires a strong current that is important for both the feeding process and the waste removal process. One of the most beneficial things that we have found for keeping the large Dendronephthya is the use of small power heads that are positioned below and behind these corals. By placing one of these small power heads behind and below the coral we are able to create a current that is constantly lifting the hanging corals. Aquarium Systems makes a small mini jet power head that has an adjustment so you can control the amount of water coming out of the pump.
The non-photosynthetic predatory corals respond very well to changing water current motion. This can be accomplished very easily using a number of power heads and timers. We are setting up a much larger display tank for our cuttings and we will be using rotating water releases made by the sea Swirl Company.
We want to report one of the most interesting feeding methods that we have developed here. By creating a large amount of foam consisting of micro bubbles it is possible to capture a large amount of protein on the surface of these bubbles. We have noticed for several years that these corals are able to capture and hold these small bubbles. By studying the large clear polyps on some of our predatory, colored Gorgonians we have been able to observe that the polyps can move the small bubbles to the central part of the Polyp. These corals are able to release the air and we are certain that this is one method these corals utilize while feeding in a natural reef environment. When I lived in Palau I learned that these corals often live in areas where the water is agitated and the current can be quite strong.
As we continued to feed our corals we found that it is very easy to make the very fine Micro bubbles that work best in this type of feeding by placing an airline below the intake of the maxi jet 1200 power head. We do not use an air stone because they tend to clog up. We have found that it is very easy to make an air release by drilling a hole in an Aragocrete Reef Plugtm that allows us to push the aquarium hose through with a slight amount of pressure. Air releases used in salt water tend to fill up with minerals. By leaving the air hose a few inches longer than needed we can push through an extra inch of airline so we can cut the the airline back to clean tubing. When we are ready to feed the aquarium we can turn on the airline and the bubbles will be released in the water current.
We are experimenting with leaving the air on to create foam for different periods of time. In our first brood stock tank most of the corals have been able to capture bubbles in about ten minutes. We have noticed that the Scleronephthya extend their polyps very far during the time that these micro bubbles are in the water column. Using this method we have noticed no adverse effects to anything in the aquarium including sponges.
Using racks to hold a collection of different bags we are able to produce several different types of food. Many of these bags are inoculated with detritus from our Grunge so we are able to produce mixed microorganisms by feeding different things to each bag. We have been able to produce a very interesting bacterial mucus that traps many microorganisms by feeding small amounts of fish oil to several of the bags. After several weeks each of these bags will have a collection of organic material that has fallen to the bottom. By placing a small siphon hose in one corner and tipping the bag we are able to collect this organic material.
In the bags that we are growing phytoplankton in we are using a dilute fertilizer that was designed for use in the wetlands. We are constantly selecting for phytoplankton that stay in the water column and do not cover the surface of the bags.
|We will continue to study more and more species of non-photosynthetic corals during the next six semesters. We are certain that people will continue to want these exotic colored corals. We will continue to report what we learn about maintaining and propagating these animals. We hope that any strains that are collected for the trade can be used to start strains of domesticated non-photosynthetic predatory corals.
We have been experimenting with symbiotic bacteria recombination. We are certain that these corals utilize bacteria that allow them to process many types of food. We have experimented with inoculating cuttings with bacteria and other organisms from several species of Nephthea that have adjusted to captivity during the last few years and are now very hardy.
If you have any information about these types of corals please e-mail us so we can share this data.
DENDRONEPHTHYA SCLERITE DETAIL
THESE TWO GREAT E-MAILS CAME THIS WEEK
From: "Ahmed Giyas"
Date: Fri, 08 Dec 2000 19:48:30 -0000
I'm fond of reading GARF.org, and I'm proud to infrom you that I have learnt a lot
from GARF, ie propagating and lot many stuff.
I just want to let you know that I have been keeping Dendronephthya since I started
keeping my marine aquarium. At that time I knew nothing about this beautiful coral,
but now I manage to grow it and do wonders with this beautiful coral.
This is what I do. I just cut branches from this coral and super glue it to pieces of coral
and then leave it to grow. Or you can cut a branch and put it between any space in your
tank that can hold it for couple of weeks, then it will start to grow on its own. I have
noticed that there are times when I take a big one out of the sea, it has got some roots
like thing. Those type of corals can be easily grown when you just leave it in the place
where you want it to be and tight it up with a cable tie or I think its called a zip tie( some
cops use it for cuffs, yeah with that).
The other thing I noticed about this baby is that it extends in the morning and
sometimes afternoon and at night.
About feeding, what I do is to put some shrimps in my blender make some ice cubes
with it and feed it with a 50cc syringe with a hose on its end.
I had not considered it keeping away form lights, cos I have no empty space in my tank,
but what I know is it really grows like that too. And the other thing is that when I see it
in the wild, there are times it grows under the hot sun, but most of them grow in caves
as upside down. But it doesn't matter either upside down or up it will grow.
Oh this is getting bit longer than I thought....
But I'm always willing to share my knowledge with GARF, because you have taught me
a lot in this hobby.
Date: Tue, 5 Dec 2000 19:35:06 EST
Looking at your pictures of the Dendronephthya it seems that they are in
direct light. I received a Dendronephthya, like the one in your picture, as
a gift. But when it is in direct light or when my main lights come on it
seems to shrink. So I have mounted it under a ledge (see attached picture).
It doesn't seem to shrink up as much but it doesn't expand as fully as the
one in your picture. I also have a Rio 600 on all the time pointed to the
front of the tank so the water deflects back to the Dendronephthya.
This same situation applies to a Red Chili (Alcyonium) I have. It is deep red
with yellow/orange polyps.
The lighting I am using is (4) 55 watts power compacts, (2) whites and (2)
blues along with (2) 48" 40 watt flourescrent bulbs, (1) white and (1) blue.
The (2) blue compact bulbs come on first, then the (2) fluorescence, then the
(2) white compacts. They go off in the reverse order.
I am going to keep experimenting and researching with these corals until I
can find what they need to stay expanded.
Any feed back would be helpful and maybe this information would be beneficial
Excuse the fuzzy picture, I am new with this.