While I and many others try to hammer the need to quarantine, there are always those who don't hear or don't heed that advice. Just take a look at the Fish Disease Forum of www.ReefCentral.com on any given day and you will see it filled with questions from individuals who incorrectly assumed that their new fish would do better in their display than in a proper quarantine tank. Once the inevitable disease outbreak occurs, they are left with the decision to tear apart their entire tank to remove all the fish to a quarantine tank for treatment, or to try one of the alleged "reef-safe" treatments available and hope for the best. The problem with these "reef-safe" treatments is two-fold. First, to the best of my knowledge these treatments have never been proven effective against their targeted parasites. Second, they also have never been proven safe for the myriad of life in a healthy, mature reef display. This latter point is the subject of my latest experiment. I wanted to evaluate whether or not these treatments would cause any mortalities to a common reef display resident. I chose Xenia for numerous reasons. First of all, Xenia can be delicate in some instances. They do not ship well and are often the first reef tank organisms to respond negatively to poor water quality. It would not be much of a test if I used something so hardy that it is difficult to kill. Also, Xenia are popular. A lot of people keep animals from this coral genus. And last, they were something that I had plenty of on hand and readily available for testing.

Methods and Materials

For this experiment, I had a specially designed acrylic cubicle system built. Its outside dimensions are forty-nine inches long by sixteen inches wide by nineteen inches high, but it is split into twelve equal compartments. Each compartment can hold almost four gallons. In contrast to most cubicle display systems at retail or wholesale facilities, each of these small tanks is completely separate from the others. No holes or overflow grids allow water flow from one tank to the next. To verify that the seals were good, I filled every other compartment with tap water and let the display sit for a day while watching for leakage. None was found.

Filtration, aeration and circulation for each cubicle were provided by twelve ATI Hydro III sponge filters. Each sponge filter was powered by a White Water model LT-19 linear piston air pump fed through a 1 ¼" PVC manifold. Due to the cubicles' tall, narrow design, the airlifts created a strong rolling circulation in each compartment.

Lighting was provided by an IceCap 660 electronic ballast powering two 48" 110 watt URI Super Actinic lamps, one 48" 110 watt URI Aquasun and one 48" 110 watt Actinic White. In addition to the internal reflectors of the URI lamps, the lamps and waterproof end caps were mounted to a standard polished aluminum VHO lamp reflector. The ballast was connected to a common household appliance timer to maintain a normal and consistent twelve hour photoperiod.

Each of the test tanks was initially filled with three-and-a-half gallons of saltwater from my main display tank, as this was initial the location of the Xenia colonies. For my water, I use an Aquatechnik separate stage two resin deionization unit (Kati-Ani) and Tropic Marin Pro Reef salt mix. The water was measured to have a salinity of 35 ppt, or approximately 1.025 specific gravity at 78°F, with a Sybon Opticon Series FG100sa refractometer with automatic temperature compensation. The refractometer was calibrated prior to taking measurements with a reference sample of pure water (< 18 MΩ-cm and 0 ± 0.01 ppt). The saltwater's initial quality was checked with Salifert test kits and was recorded as follows:

pH	8.2
Calcium	375 ppm
Alkalinity	3.5 meq/l
Nitrate	0 ppm
Phosphate	0 ppm

After each tank was filled with saltwater, an approximately one-inch long fragment of Xenia was placed into each compartment. Each fresh coral cutting was allowed to roll around in the cubicle for two days. This provided maximum exposure of the cut edges to the flow. Within two days, all of the cut edges had healed over and several had already begun to attach to the sides of the acrylic cubes. At this point each fragment was placed into a PVC collar to maintain them all at the same approximate locations in the cubicles. In this way there would be as little environmental variation as possible in circulation and light exposure. The PVC collars were made by cutting ½" thick-wall PVC into ¾" lengths. These were heavy enough to keep from being blown around while also being small enough to be minimally obtrusive.

The initial coral fragment was obtained from a local aquarist's display tank (Chris Farabaugh) in Pittsburgh. It was then allowed to flourish in my display. Over time, that one cutting developed into numerous colonies/polyparies. But, since only normal growth and natural division or imposed asexual fragmentation occurred, all fragments in this test were genetically identical clones of one another. This removes any genetic component to the variability in their responses. This particular species of Xenia is commonly referred to locally as Pom-Pom or Red Sea Xenia, although no attempt was made to differentiate it to species level.

The corals were left untouched and untreated for 10 days. This was to ensure that the fragments adapted to the change in lighting and circulation, endured the stress of moving and recovered from the cutting procedure. After this time all fragments were attached to either the bottom of the acrylic compartment or to the PVC collar. They all exhibited a healthy color, regular polyp expansion and were pulsing regularly.

The only maintenance that occurred was to provide plain deionized water from the Aquatechnik unit to replace water that had evaporated. Also, each cubicle received a one-gallon water change every five days during the acclimation period for a total of two water changes, but they did not receive any additional water changes once the testing commenced. The corals did not receive any feedings at any time as Xenia is thought to be nearly autotrophic (able to produce all necessary energy from light) (Borneman, 2001 Calfo, 2001, and Calfo, 2004) and to reduce additional variables affecting how well the individual Xenia fragments did. At the end of the acclimation period, water testing was performed again on each cubicle. The results were:

Experimental Stage

At this time the tanks were labeled so that the experiment could begin. Two of the cubicles were to be positive control tanks and would receive no treatment whatsoever. Two of the compartments were labeled as negative control groups and were to be dosed with Mardel's Coppersafe at a one time dose of ¾ of a teaspoon. The reaction of the Xenia exposed to copper would give a baseline comparison to the reaction to the "reef-safe" treatments as copper is toxic to invertebrates. The remaining eight cubicles were the treatment tanks. They were divided into four groups. Each group of experimental compartments was to be treated with one of the following "reef-safe" medications: Aquatronics' Greenex, Chem-Marin's Stop Parasites or Ruby Reef's Kick-Ich or Rally.

Each medication has its own very specific dosage in regards to frequency and amounts:

I first had to convert all these various directions into a common denominator. The Stop Parasites, Kick-Ich and Rally recommended dosages were all converted into milliliters per gallon. The Greenex was left at drops per gallon as that was easy enough to dose to the cubicles. For all the treatments, the cubicles were assumed to hold three gallons of water even though each had been initially filled with 3 ½ gallons. The airlifts, close proximity of the hot VHO lighting and the low relative humidity of my home due to the central air conditioning all contributed to cause a significant amount of evaporation. This was first noticed during the 10-day acclimation period. The cubicles lost approximately one cup of water per day, requiring frequent top-offs. I did not want any instance when the recommended dosage had been exceeded due to evaporation, so I erred on the side of caution and rounded to three gallons.

I created a spreadsheet (above) to keep track of the dosing schedule as each brand has its own particular frequency. This was the easiest way to keep track of when to dose each treatment. I also used that same spreadsheet to record my observations (below) of how the corals were responding. I observed the Xenia anywhere from three to six times per day. I checked on them in the morning right before going off to work, then again when getting home, and finally before the light went out and I went to bed. But, if any of the specimens did not look good during the first two observation, I made a point of checking on them additional times. I gave a coral a less than good rating only if it looked poor every time I observed it, denoted by the yellow background color. So, in effect, every time there is a yellow box, I looked at those corals six times that day and each time the Xenia showed poor color, was withdrawn, appeared as if it was wilting or was a combination of those appearances.

Observations

Untreated, Positive Control:

These specimens continued to thrive and grow during the entire testing period. This demonstrates that there was nothing wrong with the environment that caused obvious detrimental effects to the control specimens. Results show that Xenia can and, in fact, did do well under the circulation, filtration and lighting conditions in the experimental setting. They all exhibited a healthy color, regular polyp expansion and were pulsing regularly throughout the entire duration of the experiment.

Copper-Treated Negative Controls:

Both of these corals were dead in less than 24 hours. After the first two hours they quit pulsing and contracted. By six hours the Xenia had changed from their normal light pink color to a light gray and remained contracted. After twelve hours had elapsed, the two treated corals had turned mostly white and were no longer contracted, but instead were what I can best describe as listless. They did not seem to be able to right themselves and their polyps were being blown around by the water's movement. By the next morning, nothing much remained of the Xenia. They appeared to be completely dead with nothing more than a nondescript blob remaining inside the PVC collar.

Greenex:

These corals showed no reaction whatsoever to the treatment and were indistinguishable from the untreated control group.

Stop Parasites:

These corals appeared fine until the last day of their treatment. At that point, they quit pulsing and became limp. But, they recovered a normal appearance by the next day and remained that way until day ten, when they contracted again. They occasionally extended polyps and expanded, but remained limp. I also observed during the instances when these Xenia expanded that the pinnules on their polyps were almost completely gone. Only small nubs remained where the fine, feather-like appendages should have been. While these corals did seem to be adversely affected by the treatment, they survived.

Rally:

The Rally-treated Xenia began to look bad the day after their treatment protocol was finished. They continued to appear from days four through eight. The morning of day nine, I observed that these specimens had the same look as the copper-treated negative control group. No live Xenia were discernable, only similar blobs at the bottom of the PVC collars.

Kick-Ich:

These corals, just like the Greenex group, showed no reaction whatsoever to the treatment and were indistinguishable from the untreated control group.

Day 6 Photos Day 6 - Control Day 6 - Copper Day 6 - Greenex Day 6 - Stop Parasite Day 6 - Rally Day 6 - Kick-Ich

Day 10 Photos

Day 10 - Control Day 10 - Copper Day 10 - Greenex Day 10 - Stop Parasites Day 10 - Rally Day 10 - Kick-Ich

Day 14 Photos

Day 14 - Control Day 14 - Copper Day 14 - Greenex Day 14 - Stop Parasites Day 14 - Rally Day 14 - Kick-Ich

Conclusions

While it took longer than the negative control copper-treated group, Ruby Reef's Rally medication did kill the Xenia. As such, I would hardy call this treatment "reef safe", "safe for all aquaria" or "safe for all fish (including scaless fish), plants, corals, and invertebrates" as the product packaging states. It clearly was not safe for the Xenia in my controlled experiment.

As for Stop Parasite, I am not prepared at this time to draw a conclusion. At best, I would say my testing was inconclusive. The Xenia did appear to react poorly to the treatment, but they did not die. At this point, I do not feel comfortable making a definitive statement on whether or not it is "reef-safe," although I would be hesitant to use it in my own display.

Additionally, please remember that even though the rest of these treatments were not lethal or apparently harmful to Xenia, I have performed no experiments on their effectiveness on their target diseases, nor do I make any recommendations for their use. On the contrary; in my mind, much more testing would be required to determine if these drugs are truly "reef-safe." Other experimental organisms that would be interesting to test would be sponges, feather dusters, brittle stars, Mysis shrimp, copepods and amphipods. I would very much like to know how these animals behave when exposed to these treatments because, to me, a reef aquarium is much more than simply corals and fishes. I am very much interested in the multitude of smaller plants and animals that inhabit a healthy reef display. It is only when all these other plants and animals are tested that I would consider attempting the final hurdle of determining if the medication was effective. Numerous treatments have already been scientifically proven effective that are not "reef-safe." As such, I can't see much use for these drugs if they cannot first pass these sorts of evaluations.

References:

Borneman, Eric. 2001. Aquarium Corals. Microcosm/T.F.H. Publications, Neptune City, New Jersey, pages 62 and 153.

Calfo, Anthony. 2001. Book of Coral Propagation. Readingtrees.com Publications, Monroeville, Pennsylvania, page 302.

Calfo, Anthony. 2004. "To Pulse or Not to Pulse?: Identification and Behavior of Xeniid Corals in the Aquarium Hobby." Reefkeeping Online Magazine, February 2004.
http://reefkeeping.com/issues/2004-02/ac/feature/index.php