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Pest-free Reefkeeping Articles

Discussion in 'Husbandry' started by jahmic, Jun 7, 2013.

  1. jahmic

    jahmic Shark M.A.S.C Club Member

    Although I think being completely pest free is next to impossible...I found the first of these articles on the Reefs Magazine website a while back, and figured they'd be worth sharing.




    ...and just in case these links are ever moved/deleted...full text/photos below:
  2. jahmic

    jahmic Shark M.A.S.C Club Member

    Pest Free Reefkeeping

    by Paul Whitby

    More and more frequently these days I hear horror stories of tanks wiped out due to the inadvertent introduction of a pest that devastated the system. As I look closer at a lot of these killer incidents it appears that the pest in question is usually something that is relatively easy to deal with, but the approach taken to ridding the tank of the pest caused more damage than the pest could ever have done. A lot of this is due to ignorance of the actual dangers of the pests that we commonly encounter, coupled with a plethora of snake oil type remedies that promise almost magical whole tank cures, yet rarely seem to deliver. My purpose behind these articles is to show you what to look for, how to deal with it and possibly prevent problems before drastic measures have to be taken. Where possible I will try and give both the chemical (quick) cure as well as the biological (slower) approach. It is likely that you will be able to utilize both of these tactics to eradicate the pest and then keep them out. I would also urge you, before attempting any eradication strategy, to read, read and read some more. This is your tank we are discussing and only you can make an educated decision about the best overall tactics to choose. There are a lot of pests in this hobby and for the most part they can be easily dealt with - so if you have an unfriendly organism show up, sit back, relax and read all about them here. Finally- dont panic...unless of course you are unfortunate enough to have something worth panicking about.

    For now we will start with a few of the most common and easily dealt with beasts-- aiptasia and majano anemones.



    Aiptasia are small brownish semi-transparent anemones that seem to pop up in every system. They are commonly introduced as tiny specimens on live rock, sand or corals that have been added to the tank. They are photosynthetic as well as being voracious feeders on anything unlucky enough to come within reach of the tentacles. For the most part they remain small, but I have seen some approaching 4-5 inches in size. Such beasts are easily able of catching small fish and certainly stinging them, if not devouring them. The main problem with aiptasia is that they rapidly reproduce and seem to be one of the fastest growing and spreading of the corallimorphs. It is likely that aiptasia are one of the first pests a new reefkeeper will encounter and the panic that normally follows the identification of a single aiptasia in a tank can result in a strip down of the rock and all manner of other curious behavior. In essence, aiptasia are very easy to remove from a system and should never constitute a problem. There are numerous ways in which a hobbyist can clear their system of these critters.


    Majano Anemones

    Majanos are also anemones and are somewhat similar to aiptasia. Like aiptasia, majanos are multi tentacled with an oral disk. They are however, often much smaller and generally more substantial in appearance. They very much resemble tiny bubble tipped anemones. They can come in a variety of colors, from a drab brown species to iridescent greens and reds. As such they are sometimes deliberately added to a system by an unsuspecting hobbyist. Majanos can reproduce very rapidly, and this is the fundamental issue with these pests. One soon becomes many and ultimately a small field of stinging tentacles is present that kills all of the adjacent corals. They can also spread quite rapidly through the water column of the tank and appear in multiple places, where they once again proliferate. In essence, like aiptasia, they can soon reach plague proportions.


    Aiptasia and Majano control

    Like most pests we will encounter, aiptasia and majanos can be dealt with both chemically and biologically. I am a big fan of using both, when the chemical option has no long lasting effects on the tank. By doing so, you will immediately remove the most prominent pests and those killing corals while the biological control will find all of the other anemones that you cannot see and stop them from re-infesting the tank as time goes by.

  3. jahmic

    jahmic Shark M.A.S.C Club Member

    Chemical Eradication

    There are a number of tank treatments on the market for aiptasia and majano eradication, and for the most part they all seem to do equally well. The two that I have used and been very happy with are Aptasia-X and Joe's Juice. Both of these are a thick paste like substance that sticks to the nuisance anemone and rapidly dissolves the body. Both products come in a small bottle which contains more than enough fluid to kill literally thousands of pests. Also included in the packaging are a syringe and a set of angled wide bore needles which allow access to the hard to reach spots. Treating aiptasia with either product is very simple. You simply draw up some of the milky fluid into the syringe, attach the needle of choice and then stealthily creep up to the aiptasia or majano and squirt a tiny amount onto the head. Almost immediately the pest will begin to melt away. Should the aiptasia or majano retract into a small hole, simply follow it into the space and treat it there. Once one is treated, move on to the next. As a small tip- I have found it beneficial to turn off the pumps while doing this. If your tank is very heavily infested I would suggest that you treat part of the tank, kill the pests and put the pumps back on and move to another part another day. Remember that both of these products are chemicals, and while they are relatively safe, minimal treatment is always the best course with a tank. They do however have another drawback which is you are limited to killing only the aiptasia or majano you can see, and if you can see one, there are many more hiding in nooks throughout the tank- so expect them to return to the visible parts of the system over several weeks. In reading various forums and threads regarding aiptasia and majanos, there are a lot of suggestions for homemade alternatives to these products. Of them all, concentrated Kalk is the only one i would suggest as a cheap alternative.


    Biological control

    Berghia nudibranchs (B. verrucicornis) Of all the biological controls available for aiptasia, probably the most effective are the berghia nudibranchs. They will not eradicate majano anemones. Berghia are small worm-like creatures, about 1 to 1.5cm long that eat only aiptasia and nothing else. As such, they are excellent predators of the small anemones. Berghia are commonly available through online vendors and are relatively inexpensive. The downside is that a single animal is very slow at eradicating an infestation and is more than likely to be itself eaten by a wrasse before it can do much in the way of aiptasia control. For this reason, it is desirable to add a lot of Berghia to a tank. At first sight, this could appear to be an expensive proposition, however berghia breed like crazy and inside a few months several Berghia can become several hundred. This makes Berghia an excellent group buy and breeding project for local clubs to get the membership involved in. At the bottom of the page I will detail a simple breeding station for these nudibranchs that can easily generate several hundred juveniles from a few adults.



    Using Berghia in a tank system is easy. One simply adds them to an area of the tank, away from aiptasia and preferably in the dark. I use a wide bore turkey baster for moving these small creatures from the breeding chamber to the tank, I would also recommend temporarily turning off the pumps and allowing the berghia to settle to the rockwork before restoring flow. Do not be tempted to add them to an area of heavy infestation, aiptasia will devour berghia if they are able to sting them with their tentacles. Once added, the berghia will disappear and, over a period of several months, they will eradicate all of the aiptasia in the system. As I said above, many will fall prey to wrasses as well as shrimps in the system, some will breed inside the tank and it is likely that a stable population will be established if enough are added in the initial phase. I would recommend at least three are added to a nano and one per 20 gallons tank volume on larger systems. Once all the aiptasia is devoured, these little creatures will die through lack of food, but they can always be passed along to another hobbyist should that be the case.

    Peppermint Shrimp. (Lysmata wurdemanni) Though these small reddish shrimp are often touted as a cure for aiptasia, my personal experience is that they can be hit and miss. I have also known them to be a little less than discriminating in what they choose to eat, so keep an eye on their feeding habits if you can. They will not eat majano anemones. For the most part, best results seem to be obtained with juveniles approximately 1.5-2 cm in size. When purchasing peppermints, ensure that you receive what you seek. Often, camel back shrimp (Rhynchocinetes durbanensis) are confused with peppermints. These will not eat aiptasia, but will happily devour many of the soft corals in a system as well as sea apples and brittle stars. The key to identification is the distinctive hump on the back of the camel that is absent from the peppermint and the clear rostrum (or beak) of the peppermint and the white striped rostrum of the camel. A group of 5-6 peppermint juveniles seem to do best and will provide long term protection from future infestations.


    Butterfly Fish Another animal with an appetite for aiptasia are the butterflys. Over the numerous years I have been reefkeeping I have seen copperbands (Chelmon rostratus), pearl scale (Chaetodon xanthurus), raccoon (Chaetodon lunula) and long nose butterflys (Forcipiger flavissimus) eating these small pests. Most of these fish are readily available in the hobby however their longevity in captivity can be quite short. This could be due to various feeding requirements of individual fish, coupled with a lack of captive breeding. As these fish are caught as young adults they have already established feeding preferences and getting them to eat alternate foods can be an issue. In the wild, and in your tank they will devour small worms, fan worms and other sessile invertebrates- often eradicating all of these small critters. Before purchase, ensure the fish you have selected is eating a food you can readily supply to your tank. Small meaty foods such as mysis seem to do particularly well. As with peppermints, not all will eat aiptasia, but most will, hovering above the offending pest and sucking it into their small mouths. Watching these fish hunt aiptasia is most gratifying.

  4. jahmic

    jahmic Shark M.A.S.C Club Member

    Aiptasia eating file fish (AEFF). (Acreichthys tomentosus) These fish are a relatively new addition to the hobby and as such are creating quite a stir. They are voracious predators of both aiptasia and majano anemones. It is this fact that makes them especially desirable. The AEFF is often seen for sale as a young adult, approximately 3 cm in length. It is likely that at the time of purchase the AEFF is doing its utmost best impression of a dead leaf floating around in the water. Do not let this meek appearance fool you, these small fish can, and will, move extremely fast should you try to catch it. They are relatively easy to acclimate to our systems and seem to accept a variety of foods, mysis being preferred. Once the fish has gone through quarantine, is eating happily and is now in the tank, it is likely that it will appear to do nothing to the aiptasia population. For some reason it usually takes these guys about 10-14 days before they begin to eat aiptasia. Once started there is no stopping them, and in a few weeks all of the pests will be eradicated. The same goes for majano anemones. Of course, there is a down side to such wonderful pest controllers. Sadly, some AEFF also appear to enjoy snacking on a variety of other items in the tank. I have seen them eating zoanthids, yellow polyps, palythoa, LPS and numerous other corals. Normally they seem to take a liking to these other corals after the aiptasia/majano issue has been resolved. Fortunately, they are easily captured as they are almost lifeless during the dark hours. It is common for them to attach to a rock or other such substrate at night and resume the mimicry of a leaf. Simply turning the lights on in the middle of the night will allow you to catch the fish and place him in a tank where he will not cause trouble. My experience is that about 25% of AEFF go rogue after eating aiptasia and about 10% never touch the pest anemones. Since these fish are very hardy, they are great to be passed from system to system (with suitable QT between moves).


    Breeding Berghia

    The propagation of Berghia is a very simple process as they are extremely prolific breeders. So long as potential predators are not introduced in to the system, the babies are easily raised to adulthood. The equipment requirement is minimal. All you will need is a small tank, an air pump and hose, a few adult Berghia and a steady supply of aiptasia.
    Should you decide on this, and you have space, I would recommend a 10g, or smaller, tank as ideal. What I do (and feel free to modify this to suit your space and needs) is half fill the 10g tank with fresh saltwater and place a mark on the side of the tank at the water level. This is then placed in a sump in an area that is either unlit, or only dimly illuminated. I do this such that the water of the sump helps retain a constant temperature of the water in the tank while preventing an algal outbreak. Once sited, I take the air pump with the hose and set it up that it slowly bubbles air through the water in the breeding tank. The flow needs to be low enough that it does not create significant water movement, but does break the surface tension and film that may form. Once set up and just before the Berghia arrive, I add a dozen or so aiptasia to the system. Ideally these need to be scraped from the glass of the tank as opposed to using pieces of rock with aiptasia attached. The reason for this is to avoid the inadvertent introduction of pests such as copepods and bristle worms which will eat the berghia eggs and young. I also like to add some rubble to the system, clean dry frag disks, or some larger coral rubble that has been cleaned is ideal. Once established, I order the berghia. Generally I will order 6 adults. These need to be slowly acclimated and then carefully added to the breeding tank in an area away from the aiptasia. Once added, stand back and let nature take its course. Inside a few days you will notice the aiptasia has been eaten, so the regular addition of new aiptasia is a must. You will also notice small white sworls of eggs, as shown in the images below. After a few weeks tiny white speck can be seen that rapidly grow to usable size of 1+ cm. Obviously as the population of Berghia increases, so does the collective appetite and thus lots of aiptasia need to be added. In the past I have set up a second tank to breed aiptasia to help supply the demand for food. As the adults are observed, they can be removed and added to the display tank to eat the aiptasia there. This can be done with a wide bore turkey baster or by transferring small rocks with berghia on them. While the breeding station is running, it is important to keep the salinity stable- this is the purpose of the mark where the original water level was. Top the water back up to this level frequently with RoDi water. Water changes should also be performed to keep the water fresh. Following this simple plan will rapidly generate dozens upon dozens of sub adult nudibranchs for your system.

    In the next issue we will focus on some of the slightly nastier pests, flatworms!

    See you then.
  5. jahmic

    jahmic Shark M.A.S.C Club Member

    [h=2]Pest Free Reefkeeping II[/h]
    By Paul Whitby

    In the first installment of this series we discussed the eradication of two common pests, aiptasia and majano anemones (which can be read here). While these two pests do not really move around a tank a great deal, they do spread rather fast, which is the main reason people rush to eradicate them. They are also very easy to see and identify in your system. Next, we will turn our attention to a few wee beasties that are not so easily seen, are capable of moving and that are also capable of causing a great deal of damage. This article is dedicated to the coral eating nudibranchs that we may inadvertently introduce into our systems.

    Coral Eating Nudibranchs

    In the last article I introduced you to a coral eating nudibranch, but one often farmed for the fact that it eats aiptasia. Berghia verucornis, like most nudibranchs will eat only one type of food stuff, in this case aiptasia. Likewise the two aeolid pests nudibranchs commonly seen in the hobby are also named for their feeding habits- the montipora eating nudibranch (MEN) and the zoanthid eating nudibranch (ZEN). Like many pests, these are often brought into the tank on a coral that appears otherwise healthy and over several months the population increases to the point where the damage becomes more and more visible. Both can be readily dealt with, but there are no whole tank treatments at this time, thus prevention is by far a better strategy than eradication.


    Montipora eating nudibranch (left), Zoanthid eating nudibranch (right)​

    Of the two nudibranchs, the MEN are by far the easier to spot. The Adults are approximately 1/4 inch long and the body and surface exposed gills are bright white with a stringy, almost knotted appearance. By contrast, the ZEN are normally a dull brown color, slightly longer than MEN and with various gill coloration that tends to match the color of the zoanthids they are predating. It is likely that this camouflage is brought about by incorporating the pigments of the consumed zoas into the body of the nudibranch. In the image you can see two ZEN, both with a speckled gill coloration matched to the zoas they have been eating. This makes them extremely difficult to spot as they move around inside mats of zoas. In general, you can spot MENs on the affected coral but ZENs are more often seen on the glass of the tank than on the affected piece. Should you have ZEN in your system, it is likely that you will notice the failure of the zoanthids to open fully and the slow decrease in numbers of each colony. It is still unlikely that you would see the nudibranch itself. MENs are much easier to spot and the damage is quite clear. A slowly expanding region of bright white tissue will begin at the edge of the coral and this will get larger each day as the MENs feed on the living tissue. As the adults get larger it also possible that you will see them on the tissue, especially if you look at night as they are nocturnal. The exact life cycle of these two pests is unknown and controversy remains over whether they can reproduce asexually or not. Irrespective of this, masses of around 100 eggs are laid that hatch in 2-4 days. The young reach maturity 2-4 weeks after hatching. The egg masses of the MEN are small and somewhat tufted, like tiny grains of rice stuck together and always found on the underside of the affected coral, or on an adjacent rock. By contrast, ZEN egg masses are small mucous coated spirals on the sides of zoanthids within the infected mat (an example of a ZEN egg cluster can be seen in the photograph below). Both are tiny and difficult to spot.

    Montipora eating nudibranch on tissue
  6. jahmic

    jahmic Shark M.A.S.C Club Member


    The best treatment is to not introduce these pests to your tank in the first place. There are several approaches one can take, with QT of each coral the absolute best. However, most people do not have the facilities to isolate each coral separate from all others and thus various commercial dips and treatments have been developed. Unfortunately there are no dips on the market capable of killing the eggs of either species and these kill only the adults. Thus, it is strongly recommended to observe any untoward creatures that are released from the coral during a dip, as opposed to presuming the coral is safe to add to the tank. As an alternative to chemical dips I have often used cold tank water as a simple non-stressful method to remove potential parasites. Should you wish to do this, take some tank water and place it in a jug in the refrigerator for a few hours. The new or infected coral is then dipped and swirled in this water for about 30 seconds or so. During this time, the cold stuns the parasites and the agitation forces them to release from the coral. The coral is then placed back to a holding tank. Once done, I will check the cold water and look for any pests I can see. In general there will be small shrimp, bristle worms and other benign flora, but any nudibranchs (or other pests) will be readily spotted. If no pests are spotted it is likely that the coral is not infected, however if suspect nudibranchs are observed you are now better armed to deal with the potential threat. Should you be unfortunate to spot a nudibranch- of any kind- consider it a pest. The first step to eradication is to kill the adults to prevent further damage. The cold water dip will certainly help, but something a little more toxic such as one of the proprietary treatments on the market is recommended. There are many to choose from and most work well on adults, but any visible egg masses need to be removed by hand. Thus a series of dips spaced over several days to weeks are recommended before one can be confident (but never sure) of eradication. Please note- chemical dips are likely to be stressful to your coral so exercise as much caution as possible when performing repeated dip treatments. Besides proprietary solutions, there are reports from the literature that suggest levamisole treatment kills adults, but can also damage corals. Another option is potassium permanganate treatment which also kills adults but with minimal impact to the coral. This chemical requires care in its handling and an exact dosage needs to be used. With all of these treatments, it is strongly recommended that a great deal of research is done before use.

    While prevention is the ideal, it is not often apparent that an issue exists until a coral looks damaged. By then it is unlikely that the coral has encrusted on the rockwork and removal and cleaning of the coral is no longer an option. It is also likely that other corals in the tank may be asymptomatically infested with these predators. In this scenario two options are available. The first requires fragging all of the individual corals you wish to keep, at areas with no visible signs of damage. Where possible, select areas which have no live rock attached. Each frag needs to be treated as if it were a new specimen and dipped prior to moving to a QT system. The main display tank is then stripped of the remaining coral that may be affected by the suspected pest and allowed to go fallow for several weeks to several months. As nudibranchs only feed on one thing, any that remain in the tank will die in this period. The surviving, pest-free frags can be returned. While this process is drastic, it is the approach most likely to succeed.

    Montipora eating nudibranch damage

    Another option is to live with the pests and keep the population to a minimum using a combination of biological and mechanical control of the pests. Should you adopt this approach, taking frags of all the affected coral is still advisable should the long-term plan fail. Once the choice pieces are fragged, a program of systematic eradication can be attempted. In the case of the MEN, the approach is made easier by the highly visible parasite. This is not the case with the ZEN. For both, it is important to remove as many adults as possible and keep the population to a minimum. This is best done by observing the tank at night as both pests are nocturnal and zoanthids are more likely to be closed. Arm yourself with a siphon tube, toothpicks, tweezers and a flashlight. Ordinarily a red LED flashlight is the ideal tool for observing nocturnal shenanigans- but in this case a bright light is required to clearly illuminate the scene.

    The best time to look is several hours after the lights go out, then light up any affected corals and immediately remove any visible parasites before they return to the shade. In general, the MEN are readily removed by suction, while ZEN may require plucking with a toothpick followed by suction. A neat trick it to attach a toothpick to the end of the siphon hose with an elastic band, which facilitates the removal of any parasites released from the coral. Also, in a tank with ZEN, they will also be found on the glass as well, making removal easier. This needs to be repeated nightly until there are no more adults found. It may be that during this time the corals are irretrievably damaged and death ensues (which is why it is always a good idea to frag each piece once a pest is perceived).

    Montipora eating nudibranch

    There is however one other trick that seems to work well after the first few days of picking at adults. The technique is based on the initial cold water dip approach for removing pests and is quite simple. During daylight, when the fish population is out and about, and the tank needs a top off of freshwater, take the pipe that you are using to add water and direct the outflow directly into, or over the affected coral. Ideally the freshwater should be cold and the flow strong enough to blow the detritus out from around the coral. The inrush of cold water stuns the hidden adults and sub adults and releases them from the coral tissue. Once released they pass into the water column where it is likely that hungry fish will snack on them. This is also a process that needs to be repeated, but one which can rapidly reduce the numbers of adult pests on a coral. Observing what is blown from the corals will give an indication of the level of infestation. This is an ideal approach for scrolling montipora and zoanthids as the water can easily penetrate the spaces between the plates/polyps. Having several wrasses in the system will certainly help with devouring any nudibranchs released from the coral before they can reattach to the rocks.
  7. jahmic

    jahmic Shark M.A.S.C Club Member

    Biological Control

    Mystery wrasse (left), Yellow coris (right)

    In the above paragraph I eluded to the fact that wrasses will eat free floating nudibranchs, however many wrasses make their living hunting small invertebrates on corals and reefs. This habit can be used to our advantage with the long term control and prevention of infestation of both ZEN, MEN and many other pests. There are an enormous variety of wrasse species available in the aquarium trade, however some are more suitable than others when it comes to pest prevention. To my mind, the best species based on size, cost and beauty of the fish are the smaller Pseudocheilinus species such as the aptly named Sixline wrasse (P. hexataenia). While slightly larger, and certainly more costly, the mystery wrasse (P. ocellatus) is also another great pest predator. Both of these fish are best kept at one per tank due to aggression. As an adult, it is not uncommon for a larger Sixline wrasse to dominate the tank and attack any like colored new additions. Aggression with the Mystery is more limited to other Mystery wrasses. Other wrasses that I strongly recommend include several members of the Halichoeres and Macropharyngodon species. With regards the Halichoeres, my personal favorite is the yellow coris (H. chrysus). This bright yellow wrasse is extremely adept at poking between folds of corals and the deeper recesses of scrolling montipora. Since they only achieve a few inches in size as an adult, Yellow wrasses are an ideal choice for most tank setups. Unlike the Pseudocheilinus species, these can be kept as pairs with the added advantage that more often than not, they will spawn every few weeks. Other Halichoeres species include the beautiful Marble or Checkerboard wrasse (H. hortulanus) and the Melanurus wrasse (H. melanurus), as well as a variety of other species.

    Marble wrasse (left), Melanurus wrasse (right)

    In general, juveniles make ideal tank mates but many grow quite large and soon become a pest themselves. While they do not specifically harm things, they are prone to turn over quite large rocks in their incessant hunt for invertebrates. Most, if not all Halichoeres species require a soft sandy bed to sleep in and are not suited to bare bottom systems. The Macropharyngodon are less prone to destructive behavior as adults, but can be somewhat problematic to acclimate to a captive environ due to their preference for live prey as food—exactly what makes them exceptional pest police for your tank as they will constantly hunt for food. This family includes some of the most striking colored fish such as the Leopard wrasse, Potters wrasse, and Dusky wrasse (pictured left to right below). All of these will cohabit with each other and other wrasse species.

    Leopard wrasse (left), Potters wrasse (center), and Dusky wrasse (right)

    The inclusion of wrasses in a new system will certainly help as a prophylactic approach to pest control. The only downside to a heavily wrasse populated tank is that they will hunt and eat any Berghia verucornis (aiptasia eating nudibranchs) that you may add as part of the aiptasia control mentioned in the last article. This is the reason why it is better to farm Berghia in a separate system and add young adults to the infected tank to keep a steady population.

    In summary, the coral eating nudibranchs are voracious predators that can rapidly infest and devour corals in a display. A combination of vigilance with new and old acquisitions as well as housing a wrasse or two in a system will certainly help, and hopefully prevent loss of corals to these pests.
  8. jahmic

    jahmic Shark M.A.S.C Club Member

    [h=2]Pest Free Reefkeeping III: The Flatworms[/h]
    Paul Whitby

    If you have been following this series of articles you should now have a good handle on how to treat pest aiptasia, majanos, and those dreaded nudibranchs. All of these can be readily killed in or out of the tank. Those are the easy pests to deal with. In this, the last of the three articles on pests, we turn our attention to the real nasties-the flatworms. With that being said not all flatworms are a major cause for concern. Some are totally innocuous and are a vital part of the marine microflora. Their brothers and other related species however pose a very real threat to the long term viability of a marine system. These guys are the masters of disguise, they are subtle killers that creep around at night, hide behind corners and occasionally grow so large that they will truly freak you out. So, without further ado, let’s look at the common flatworm pests we may encounter.

    Not all species of flatworms cause problems in aquaria, but...

    Common Pest Flatworms
    The first group of flatworms that we will look at are the Convolutriloba species which includes the very common white and the red flatworms. These are often seen on the glass of the tank, usually in the corners or by the sand margin. Low levels of infestation are often difficult to spot and high levels of infestation are more of a nuisance than a major threat to the corals in your system. The overall morphology of these pests are very similar to the classical planaria we all learn about in high school, an elongated body with a lobed, or pointed lower trailing end. They can be surprisingly fast movers and apparently glide over surfaces using the ciliated underside. The white varieties very much resemble Casper the friendly ghost, both in appearance and also in their nature. These types do not cause a problem and mostly predatory on small pods throughout the system. My personal experience is that these are generally seen in the refugium as opposed to the main display. The red type, however, are not as friendly and can rapidly reproduce within your tank. Apart from looking a mess, the large numbers ofConvolutriloba compete for foods that other scavenging organism would otherwise consume. This can have the potentially to lower the overall level of biodiversity and micro fauna you have within your tank. In general, the red Convolutriloba seem to avoid corals (contrary to popular belief-they do not eat coral) but much prefer to hang out in the cracks and recesses of live rock where their prey also lives. Mild infestations may well go un-noticed; however, worms can be seen during a population explosion - commonly they will be seen on the caps and stalks of toadstools, as well as assorted mushroom species.

    As with all pests in this series, prevention is far better than attempting to eradicate these nuisances. They are readily killed by the vast majority of proprietary treatments on the market. Revive, Coral Rx, RPS all Out and even Iodine treatment will kill Convolutriloba species. Since these animals reproduce by fission (splitting) there are no eggcases to worry about and a simple dip, following the manufacturer’s directions will pretty much guarantee the death of all hitchhiking red flatworms.
  9. jahmic

    jahmic Shark M.A.S.C Club Member

    Control of Red Flatworms

    A Red Flatworm infestation on the glass of a sump.

    Red Convolutriloba populations are very much controlled by nutrient availability in the system. Detritus accumulation leads to an increased pod population, which leads to an increased flatworm population. For the most part, the levels of these critters will wax and wane for no apparent reason. My personal experience from several years back, is that the visible population will slowly increase becoming more and more noticeable until one day, for no apparent reason, they will just simply disappear with only a few ever visible thereafter. This likely reflects nutrient flow within the tank. Should you find yourself in a position where you cannot wait for them to just go away on their own, they can be easily controlled (biologically) or eradicated using a whole tank treatment, but this is not without its own inherent set of risks.

    Biological control is once again afforded by the wrasses. In the previous article I discussed several predatory wrasses and all of the aforementioned wrasses are excellent at controlling the population of these critters, though six lines seem to do the best job. There is however, one other fish that is surprisingly adept at hunting and devouring red flatworms, that is the common blue or Springers damsel (Chrysiptera springeri). These guys are relatively cheap and are not overly aggressive, unlike some of the other damsels. They do, however, have quite the appetite for flatworms and will certainly help bring a population explosion under control. Another option is to add a few velvet nudibranchs (Chelidonura varians) to the system. These solely predate Convolutriloba species and will literally mow them down. Being small and motile they can get to places you cannot reach with a siphon. They are however omnivores, and once the flatworms are consumed the nudibranch will most likely die.

    [​IMG]Many types of fish, such as this six line wrasse, feed on flatworms.

    Should biological control not be your method of choice, there is always the option of a whole tank eradication program. This is most readily performed using Flatworm Exit (FWE) by Salifert. There are however precautions one needs to be aware of prior to using this product. The problem lies with the biology of the flatworm, not the chemical used to treat with. As flatworms die they release a large number, and amount, of toxic compounds that are normally sequestered inside the body. A fish feeding on live flatworms is not affected by these, one feeding on dead worms is rapidly overcome and may die. Thus it is essential to remove as many flatworm as possible prior to initiating treatment. Siphoning and collecting in a mesh bag will remove many visible Convolutriloba, but many, many more will remain in the rock work. For this reason, several siphonings over a few days is recommended. It is also important to treat the entire tank, refugium and skimmer etc. with the medication. Another issue that is becoming more prominent is an apparent resistance to FWE. To ensure you hit the correct dosage it is recommended that you siphon around 20-50 flatworms into a container with 1 gallon of tank water and add FWE at the recommended dosage and gently stir. If the dosage is correct the worms will begin to show stress. Initially they will contort and start to move more rapidly. The death is preceded by the worm detaching from the surface. Should this not occur, add more FWE (recording the number of drops) until the worms begin to die. Multiplying the final amount by the tank volume will ensure a successful treatment. As treatment is applied to the tank, attempt to manually remove as many dead, or dying flatworms as possible - blowing a powerhead into a clean filter sock, adding clean filter socks to all overflow outlets, etc. will really help. Following this precaution will give your fish the best chance of surviving the toxin release. One technique I have thought of that may help with fish death - but not tried - is performing this treatment at night when the fish are asleep, and not feeding. Lights over a sump would be sufficient to ensure there is death, but catching released flatworms would be difficult. Care also needs to be taken to ensure that any crabs and or shrimp that may be susceptible to this treatment are removed. It is strongly advised that you do an extensive amount of research on using FWE prior to use. It does work well, if the instructions are followed carefully.
  10. jahmic

    jahmic Shark M.A.S.C Club Member

    Leopard Polyclad Flatworms

    Mollusc-Eating Leopard Spotted Flatworm.

    One of the most alien creatures I have ever encountered on my journey through reefkeeping are the Leopard spotted polyclad flatworms. Unlike the Acoel flatworms described above, these are large flatworms with a much more advanced body structure. They can reach several inches in size and generally have a ruffled or frilled ridge. They can grow so large that when they move it appears that the entire rock is simply flowing from one spot to another. They are remarkably adept at hiding and are voracious predators of mollusks.

    Unfortunately, this includes the prize Tridacna clams we often include in our systems. There is no effective whole tank treatment for these predators. Fortunately, it is likely that any one tank will only host one or two at a time. Unlike the Convolutriloba, these flatworms do not make their presence known, a dead snail here and there is hardly cause for concern, however the untimely demise of a clam may indicate one of these guys is lurking in the rock work. There are no easy ways of eradication - they are too large for wrasses, FWE is ineffective and the only way to kill them is to isolate the rock they are hiding in and treat with one of the more toxic chemicals described above until you are certain the beast is dead. I have isolated these flatworms before and they are remarkably resistant to starvation - lasting several weeks in a plain glass jar with no heat or waterflow. Should you suspect you have one of these larger flatworms in your system viewing the tank at night, under redlight, should aid in identification. The possible baiting of the tank with live feeder clams may also draw them into the open. So, based on the difficulty of eradication, prevention, through quarantine is really the best course of action.
  11. jahmic

    jahmic Shark M.A.S.C Club Member

    Acropora-eating Flatworms

    An image of an isolated Acropora-Eating Flatworm (AEFW).

    Of all the flatworms one could be blessed with having, these are truly the worst of the bunch. At the beginning of this series of articles I stated that when you find a pest, you shouldn’t panic… well AEFW are pretty much the exception to the rule. Once these are acquired, and detected, you either have to drastically change your habits or remove all your prized Acropora species. There are no in-tank eradication methods, biological control is sketchy at best and manual eradication is all but impossible. Once again, prevention is way better than eradication with these critters. Unlike many of the other pests in this series which are readily visible, the AEFW is extremely well camouflaged and almost impossible to see in a marine system. Their biology and ability to disguise themselves is discussed by Dr. Kate Rawlinson in an article in this magazine. Within that article she mentions that “the Acropora species affected by the AEFW include Acropora valida, A. pulchra, A. millepora, A. tortuosa, A. nana, A. tenuis,A. formosa, A. echinata, and A. yongei.” Of these, the two Acropora species that are the best indicator of infestation are A. valida and A. nana. These are relatively thick based, making viewing easier, but it is the light tan coloration of the coral that allows the easy identification of the small circular bite marks. These lead to an almost speckled appearance in the more shaded area of the coral and this is a clear indicator of a problem. Another indication of AEFW presence are eggcases. These are small dark brown spheres laid in a geometric pattern almost having the appearance of a tiny brown beehive. In her article, Dr. Rawlinson states that each egg can contain multiple embryos which hatch and immediately begin feeding on neighboring coral tissue. Considering that a single animal can lay multiple eggs, with multiple embryos, multiple times, it is not hard to see how a few AEFW can rapidly over run a tank.

    Typical bite marks from an Acropora Eating Flatworm infestation.

    So let’s assume the worst has happened, bite marks are seen around your A. valida colonies and you want to know if AEFW are what you have. The first step is to make a positive identification. There are two ways to do this - one is in tank, the other is out of the tank. Clearly the latter requires you to remove the affected coral. Once removed, look for the tell-tale signs of eggs around the base of the coral. These are very easy to see in most cases and are an absolute confirmation of your worst fears. Should you wish, and since the coral is removed, you can use one of the many proprietary dips to kill the adults that are presumably roaming all over the flesh. In the past, these dips have been effective at killing adults but have not killed the eggs. Recently, a new product has entered the marketplace with claims of penetrating and actually killing the embryos within the eggcase. I have not tested this on AEFW, but it does appear to be quite the potent killer of coral associated microfauna on a series of tests I have done with it. Produced by Reef Pest Solutions, “All Out” may offer the only hope for effective cleansing of incoming Acropora species prior to adding to a tank. Reading other peoples testimonials on this - it does appear to live up to the manufacturer's claims.

    Having established that there is an infestation, a plan needs to be made to deal with this. In a tank with a few pieces of Acropora, the ideal solution would be to remove the Acropora leaving no living flesh behind. The tank is allowed to go fallow of Acropora for several months. The corals themselves need to be collected and dipped to kill the adults and quarantined in a separate system. If a dip is used that does not kill the adults, it is recommended that several dips, with a complete sterilization of the QT tank between dips, is performed. Even if “All Out” is used, I would recommend at least two dips are performed to ensure effective sterilization. After several months have passed and no more tissue loss is noted you can add the corals back to the DT and begin a more stringent QT program with incoming corals species.

    A brown "honeycomb" arrangement of AEFW eggs, each containing multiple embryos.

    In tanks that are very heavily stocked and encrusted with Acropora the above is not an option. In this case a combination of biological and mechanical removal can be used to control and limit the damage - but you can never be sure that you are ever pest free. Essentially you will have to come to terms with their presence and live with them. This may seem unacceptable to most, but once a program of control is initiated coral loss is minimized and their presence is reduced to more of a dull annoyance. This approach requires a drastic change in husbandry habits and a constant attention to the tank. It does however prevent the loss of your corals. The approach very much depends on the size of the tank, but essentially we are going to blast as many adults off of the infested coral into the water stream and happily watch our wrasses devour them as they wriggle about. In a small tank this can be readily achieved with a turkey baster. In a larger tank a powerhead with a nozzle, such as an unmodified Maxijet-MJ 1200 does the job nicely. The first time you do this it is likely that you will be amazed at how many worms you release from the coral. As disguised as they are while on the Acropora, once release they are clearly visible as small white disks. Wrasses would agree with this as they have no difficulty catching them as they are released in to the water flow. It is likely damsels will also take this opportunity for a free snack as well. This process is repeated on every Acropora and on the rock around it, as frequently as possible. Ideally this should be daily for the first week or so. It is likely you will notice a big drop in numbers over the period of a few days. This is not a sign to drop the frequency of the blasting, since the second wave of embryos will be busy moving up the coral eating as they go. After a week or so, the frequency of blasting can be decreased - though this decision should be based on the number of worms released each time. You may also notice that your [I]Acropora colonies are also starting to look great. The reason they do so is that you are now doing something that was practiced by many early reefkeepers, but has since fallen into disfavor over the years - that being the blasting of rock and corals with powerheads to dislodge and remove detritus. The periodic increased water flow over SPS helps remove accumulated slime, debris and other minor irritants (even if you don’t have AEFW, try this and see the results in a month or so). Should you take this approach, there is a slight modification of this method that may increase the effectiveness. It is known that freshwater dips will stun and dislodge AEFW. As opposed to blasting with a powerhead, at such time when a top off of the system is required, take the incoming freshwater and blast that into the coral skeleton. This will likely have no effect on the SPS but will drastically increase the number of worms released. (I would recommend testing this on non-prized specimens prior to rigorous blasting, but have yet to see any untoward effects on corals following this treatment regimen). Whichever method you choose, diligence is the key, but very soon a large infestation can be controlled to the point of it becoming asymptomatic. Do not however, ever make the mistake of thinking that the worms are gone. They are there, in small numbers hiding in the dark, hard to reach areas waiting for a lax in your attention - at which point they will begin once again to proliferate. As an aside, I have heard from several hobbyists that the wrasses in the system appear to become more adept at hunting AEFW after a month or so of these treatments. Presumably this is due to training them to accumulate around the [I]Acropora heads to catch the worms released from the coral.

    [SIZE=2]Close-up of AEFW egg mass; if you look carefully you can see the developing flatworms inside the eggs. Photo by Marcin Smok.[/SIZE]

    With this, I close this series on pest free reefkeeping. The critters mentioned in these three articles cover most of the common pests we may encounter in our systems. It is likely you are reading this series because you have encountered something that is either colonizing your tank or killing your corals. At this point eradication is your only option (if possible), but I cannot stress enough how important prevention and quarantine is when dealing with captive systems. With the increased frequency of frag swaps and the promotion of eco-friendly frag farming, it is likely that many rare pests will become more and more prevalent in the hobby. The only possible and potentially successful barrier to this spread is the vigilance of individual hobbyists.

  12. ValG

    ValG Cuttle Fish Platinum Sponsor M.A.S.C Club Member

    this should be a Sticky Thread IMO
  13. jahmic

    jahmic Shark M.A.S.C Club Member

    Re: Pest-free Reefkeeping Articles

    Looks like it's been stickied. I'll slowly work on getting the pics backed up to my photobucket account so that they don't disappear.
  14. FinsUp

    FinsUp According to my watch, the time is now. M.A.S.C Club Member

    Re: Pest-free Reefkeeping Articles

    I can't tell you how much I appreciate you uploading these articles, Khalis. They're extremely valuable. Thank you.

    Sent from my LS670 using Tapatalk 2
  15. Andrew_bram

    Andrew_bram Kraken M.A.S.C Club Member

    Pest-free Reefkeeping Articles

    Very nice
  16. holla916

    holla916 Copepod

    Great info i have recently had an outbreak of montipora eating nudi in my frag tank, going to try a few of the tips in the article to see if I can get it under control.

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