Dr. Bingman's recommended method for treating this condition with Chloramphenicol is outlined as follows:
The safest way to treat affected colonies is to put them in an isolation tank, such as a 5 gallon polyethylene bucket. Use a powerhead for water circulation and gas exchange in the bucket. A heater can be included as well, if necessary. Do not use an airstone, in order to avoid producing an aerosol of bacteria and antibiotic.
Before placing the coral in the Chloramphenicol bath, give it a 30 minute dip with 5-10 drops of full-strength Lu go Is solution per liter of seawater. This harsh treatment is designed to allow as few bacteria as possible to experience selection for resistance factors against Chloramphenicol in the following treatment.
Therapeutic doses for isolation tanks are 10-50 mg of Chloramphenicol per litre. Corals survive 2-3 days at the higher doses, but they are not happy. Bingman does not recommend treating the aquarium since it is dangerous, and it is quite possible to crash the tank because the decomposition of dying bacteria from a sand bed can rapidly consume all the dissolved oxygen. Furthermore it is unrealistic to attempt to eliminate such bacteria from aquaria...they are ubiquitous. Nevertheless treatment of the colonies when an RTN event occurs can be effective.
A 100% water exchange with fresh antibiotic should be prepared daily on the isolation tank used to treat the corals.
The old antibiotic treatment water should be treated as follows before discarding it: Put 1/4 cup of bleach per five gallons of antibiotic laden water. Mix. Hold for several hours before you discard the solution down the sanitary sewer. The bleach will destroy the remaining antibiotic and any resistant bacteria present.
When you remove the coral from treatment, give it a 30 minute Lugol's dip at 10 drops of Lugol s per liter. This will surface-sanitize the coral and hopefully kill as many antibiotic-resistant bacteria as possible. Place the coral back in the aquarium.
Bleach the treatment bucket and the dip solution, following the close-time schedule above.
Important Note: Chloramphenicol is not approved for ANY aquaculture application in the United States.
Failing to destroy the used antibiotic with bleach will result in an increase in Chloramphenicol resistant bacteria in the environment. The protocol above is not EPA approved. It will, however, destroy the chloramphenicol and any other residual organics in the water. Failing to bleach-treat the used water is extremely irresponsible.
An important factor in the occurrence of this condition is the growth of established colonies such that the water flow in the aquarium is reduced by drag on the branches. Overshading by these branches also reduces light to the lower portions of the colony, which often are the first to get white-band type symptoms. When there is such reduced water flow and light, the condition spreads most rapidly. The presence of strong water How seems to help prevent the spread of the disease to healthy colonies that are bathed in strong currents. On the subject of preventing the spread of this condition, ultraviolet (UV) sterilizers do effectively kill water-borne bacteria, so we suspect that they may be very useful in controlling the spread of this condition, or even limiting its incidence, though they cannot be relied on to effect a cure in colonies already affected within an aquarium.
From this we gather a few important tips: 1.) Keep the corals well pruned to prevent overshading and flow reduction and add more water flow if necessary; 2.) Quarantine new colonies 3 ) Always break off several branches from a new as well as old colonies to establish them in as many aquariums as possible to minimize the potential of losing the species should any of the branches become affected. 4.) A UV sterilizer may offer a safer environment for the small polyped stony corals that are so susceptible to RTN infection.
When the disease occurs, remove all affected colonies if possible. Healthy branches far away from the necrosis should be severed j *
and maintained in aquaria separate from unhealthy branches. Underwater epoxy can be used as a band-aid at the progressing front of tissue necrosis, and this may halt the progression of the disease. This does not always work on corals with porous skeletons such as Acropora since the bacteria can move within the corals as well as along its surface. Direct an evenly distributed (not a jet-stream), increased water flow over affected colonies if they cannot be removed from the aquarium, but break and remove as many affected branches as possible to avoid spreading the pathogen through the aquarium in large amounts.
Dr. Bingman and Terry Siegel have correctly recognized that this condition has serious implications for the reef keeping hobby as a whole: aquarists who have invested a fortune acquiring rare and colorful Acropora, Seriatopora, Pocillopora, and other small polyped species risk losing everything, and this can easily result in many hobbyists getting out of the hobby. We can't stress enough how important it is to maintain these species in several aquariums to be able to re-establish species that can easily be lost to disease when maintained in just one aquarium.
We are reminded of Martin Moes assertion, "Now that serious marine aquarists have a better understanding of what is required..., and access to the equipment that can provide good marine environments for many invertebrates, a lot of the more mysterious problems that we encounter are probably caused by bacteria." This statement precedes a series of fascinating accounts that Martin noticed "popped out at (him) over the years/* all cleverly juxtaposed in his revised edition of The Marine Aquarium Handbook. (Moe, 1992). The accounts relate his own experience and that of other aquaculturists and aquarium hobbyists in the management, with antibiotic treatments, of mysterious rapid mortalities in fishes and invertebrates, some caused by bacteria in the genus Vibrio. This section is one of many gems in this book. If Martin makes any further revisions to it he should include the experience of RTN as another example of bacteria causing devastating ly rapid mortality.
An article by Mike Paletta in the Fall 1996 issue of SeaScope and in the May 1997 issue of Aquarium Fish Magazine discusses the occurrence of "bleaching" in small-polyped stony corals and proposes a pathogen. Vibrio spp. bacteria. Lo and behold the same bad guys Moe discussed. Paletta's article was particularly interesting because it highlights an important error of detail that exists in both the scientific and aquarium hobbyist communities. This error surrounds the use of the term "bleaching." It is unfortunate that this word was chosen since it does not precisely convey the meaning of the several maladies that affect corals, causing them to become pale. What is causing the whitening? Are the corals losing tissue or just pigment? The question of the difference between the two options can be more basically asked: are the corals dead or just faded? Quite a difference! In large polyp fleshy corals there is no confusion since the tissue is very obvious. In the j small polyped corals there is considerable confusion since the tissue is rather thinly covering the skeleton. In these so-called "bleaching" events the corals are dying fast from tissue destruction, not from losing pigment. The title of Paletta s first article should not have been "Bleaching of Small Polyp Stony Corals in Aquaria7 It should have been "Rapid tissue loss and death in Small-Polyped Stony Corals in Aquaria."
In general, scientific articles describing "bleaching" refer to the loss of pigment, not tissue. This malady is quite different from RTN, is seldom fatal, and has numerous causes. However, it is likely that even scientists could make the same error in judgment that aquarists make about small polyped stony corals, especially when compiling statistics about "coral bleaching" based on the observations of other people around the world. When divers report bleaching events do they really know how to distinguish loss of pigment from loss of tissue?
Could anoxic sites promote the development of pathogenic strains of bacteria such as Vibrio spp.? We can't say for sure but there could be a connection. Elevated temperature (associated with both bleaching and tissue loss events in the wild) reduces oxygen solubility in the water and therefore increases the possibility of anoxic conditions in the substrate. In nature the warm season is usually also the calm season, which further increases the chance of anoxia in the substrate in the natural environment, or brings the anoxic condition closer to the substrate surface. If an anoxic environment is a breeding ground for pathogenic bacteria, then hot and calm water are dangerous conditions for corals sensitive to bacterial diseases. Coincidentally (?) coral diseases in the natural environment seem to be most prevalent in the warmer months.
Lately there has been a lot of publicity in the news about tissue necrosis diseases in corals, including the long recognized "white band" disease and more recently discovered similar conditions such as "white pox" described by Dr. Jim Porter based on affected colonies of Acroporapalmata off Key West. The news media has reported these conditions, usually associated with the need for conservation and protection from human influences (which probably have absolutely nothing to do with these diseases). At the same time avid aquarists have been writing their experience and hypotheses in E-mail communications. Mike Paletta, Terry Siegel, Stanley Brown, Bruce Carlson, Craig Bingman, Bob Stark, Larry Jackson, Greg Schiemer, and Greg Cook among others have offered interesting perspectives and described their personal experiences, losses and successes, sharing with us their views about this condition. The combined pool of experience of these people and other aquarists is an invaluable resource for scientists studying these diseases. At the moment scientists haven't got a clue about the causes of tissue necrosis diseases, if the newspaper articles are reporting their opinions accurately.
Although we have attempted to provide an especially informative text in this volume (and we know we've succeeded with that goal), it became apparent as we did the research for this book that we were only scratching the surface. So little is really known about these creatures. We know that as aquarists continue to share their ideas and publish their observations about reef aquariums, the understanding of a great many of the mysteries of coral reefs and the way their inhabitants live will be revealed.
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The word aquarium originates from the ancient Latin language, aqua meaning water and the suffix rium meaning place or building. Aquariums are beautiful and look good anywhere! Home aquariums are becoming more and more popular, it is a hobby that many people are flocking too and fish shops are on the rise. Fish are generally easy to keep although do they need quite a bit of attention. Puppies and kittens were the typical pet but now fish are becoming more and more frequent in house holds. In recent years fish shops have noticed a great increase in the rise of people wanting to purchase aquariums and fish, the boom has been great for local shops as the fish industry hasnt been such a great industry before now.