Acclimating Berghia nudibranchs, Your Aiptasia SWAT Team

Originally posted in 2006
Updated in 2025

It is very important to get your delicate Berghia nudibranchs into your reef system without injuring their foot. With this in mind, please read all of this instruction.

The top picture is a rock removed and flipped over to reveal 4 concentric rings of Berghia eggs. The next picture is a rare shot from inside the tank and under a rock. The 2 combined egg strands pictured contain approximately 800 eggs.
Some information about your Berghia: We normally ship very active young Adult Berghia unless a different size is ordered. These adults are 1/2 inch or more when hunting but are very likely to be extremely tiny after shipping. More about this is below in the section “Your Berghia Shipment”. Juveniles (“pre-adults”, “subadults”) can be used in very special circumstances but this is not the case for most reef tanks. Our adults ship well and their addition to your reef should be successful. These animals are extremely small by comparison to other animals we see for reef tanks but most are carrying real nice egg coils of over 200 fertile eggs when we select them and some may lay those in your tank soon after you get them. They develop egg ribbons every 2 to 3 days at this age. Egg ribbons may not be seen because these are very reculsive animals, living on the underside of rocks and their camo is often so good, they can be hard to see when out and about. We’ve proven Berghia are successful at controlling Aiptasia sp. anemones over and over in numerous tanks and it is our goal with this site to provide you with the information to help insure this goal is met in your system. Following the instructions on this web site will help you achieve success with them in your system. Some tanks take a few weeks to clear, some take many months. It is a matter of the biology of the Aiptasia vs the Berghia. Read our Aiptasia Biology page and reflect on the number of baby Aiptasia that can be produced in a single night to understand the time element and the need to have the correct number of Berghia.

Time Element: The big question – How long can the Berghia be expected to take to clear the tank? Every reef keeper who learns how to use Berghia correctly and gives them the time and patience they deserve will definitely be rewarded. It is worth the patience and learning to use our Adult Berghia to control Aiptasia will produce results in your reef without placing any part of the delicate balance in the reef at risk. Berghia are snails, an all natural cure. They are not racers, they are methodical purpose driven snails. Reading the articles on this site, including those linked from Learn About Aiptasia To Kill Them above will help understand the time element. While many reef tanks realize results beginning on the first day or within the first week and others may observe results in less than a month this can take far longer for others. One must be willing to allow more than 3 weeks or even 3 times that or more than 9 weeks for Berghia to start to control a completely out of control situation. After 3 months (12 weeks), the first of the baby Berghia from the initial colony will be starting to show up and in another month or two will be of size enough to help out the original colony. This partially depends on the original colony being of sufficient size for the tank to establish this working colony. Our articles also address this and the synergy that will develop that is necessary to achieve critical mass. So, after thousands of eggs, the first baby Berghia that survive in the reef will likely be counted on one hand. This is nature and why so many eggs are laid. This means in a 75 gallon tank that began with a colony of 7 little nudibranchs, we can expect to have from 8 to 15 total nudibranchs in the colony by the end of 4 months providing we have done a good job maintaining their habitat. It is safe to double this number of babies by the end of 6 months to as many as 30 babies. These estimates may be conservative. At least one of our customers was able to extract 100 adult Berghia from her reef and sell them to pay for new lights and more corals after her tank was clear. But by the time the colony is reproducing like this it will be deeply embedded in a cave and seldom, if ever seen. But for Aiptasia that have been attacked by other methods and grown huge and out of control, 8 to 15 Berghia, some babies still at 4 months is not really a large number of Berghia. This is the unfortunate part because our patience can wear very thin by now and some other solution that is not really a solution at all is likely to get the credit for Aiptasia control instead of the Berghia. Remember, the Berghia are still down under removing the Aiptasia where they originated in the first place. Down under, where syringes can’t reach and no fish or shrimp hunts. Berghia go between branching coral
2 Berghia Nudibranchs Eating Aiptasia Anemone Down Under Where They Do Their Work Unseen.
colonies, under shells and in cracks to get rid of the Aiptasia source and never will ever harm any of our favorite reef pieces. Once the necessary critical mass is achieved for your particular reef, it is then the Aiptasia will begin to be controlled. Copperbands on the other hand eat a variety of things including feather dusters and can attack clams if they are not trained. Unfortunately many Copperbands will be lost trying them as the solution. Peppermint shrimp, the Gulf of Mexico jetty predator, as it grows older can learn to attack anything with a gastric cavity. Often the tell-tale scars can be seen when the observer knows exactly what to look for. And then there are the bottled mystery chemicals month after month with what percent of heavy metal impurities? Not one of these will get deep inside the rocks where the Aiptasia came from, under rocks and shells or deep in the reef behind things yet is likely to get credit for Aiptasia control because the results can be seen instantly on the surface of the reef. There is not another method to use against Aiptasia that has the possibility to reach critical mass to achieve complete control and actually get into the holes in the live rock where the Aiptasia Larval Planula are incubating, awaiting their opportunity to bloom. While we look with a flash light at night and don’t find the Berghia, they are still in there, eating dozens of baby Aiptasia and a few larger ones each night, methodically working on the deepest parts to remove the Aiptasia source.

Our selectively bred adult Berghia are extremely hardy once acclimated into the reef. Finding the Berghia in a complex reef system is difficult. Look after the sun sets and right at sunrise on the higher current side of rocks where Aiptasia gather to extend their tentacles into the currents to feed. Berghia are hard to see because they will keep to the depressions and cracks to stay safely secured to the rocks. Their colors will begin to mimic the background of the reef making them even more difficult to see. The truth of the time element is that some people see results in a few days to a few weeks and others using Berghia may take closer to a year. But, this is the last of the Aiptasia and Berghia will not wear the reef keeper out like other methods. What accounts for the timing is the biology of the two creatures, the Aiptasia reproductive and survival scheme vs. the nudibranch. A couple dozen embedded Aiptasia will provide dozens of baby Aiptasia each week or more depending on the reef. This is paradise for the nudibranch colony and it will take time to work through all the Aiptasia. The original start up colony needs to be of sufficient size and formed with young adult Berghia to be a colony for your system. Keep the tank water parameters healthy and the nudibranch strategy appropriate, and they will get the job done. No worry of toxins, as this species is non-toxic. There is a strategy or phased approach to use for difficult tanks discussed in one of the articles on our web site. To insure your success with nudibranchs, please read this entire site. There are lots of pictures and details to help understand what is going on deep within your reef. The bottom line regarding the time question is: This could take a couple weeks to over a year in your reef. If progress is not fast enough in a particular reef system, add a few more Berghia to get the job done faster, safely preserving the reef system and life on the rocks. In our specially engineered packaging, our shipmemts arrive alive, in excellent condition and we always guarantee it!

Berghia Sensitivities: A stable marine tank system that has completely cycled and stabilized is a good tank for Berghia. New systems must be allowed to cycle completely and stabilize prior to adding Berghia. Berghia are among the more delicate and somewhat sensitive animals you will keep in your reef system. Once they are acclimated and properly inserted into your reef, they are very resilient and even somewhat forgiving of many mistakes. Water quality must be maintained in very good and reasonably stable condition. Ammonia content should measure 0 and should be maintained at 0 in a stable tank. A good growth of coralline algae indicates system stability. If you experience seasonal die offs or brief ammonia or nitrate spikes in your system, serious fish diseases, have used medications or flatworm treatments, these should be corrected prior to adding Berghia. Berghia also cannot tolerate acclimation under your system lighting as they have proven to be sensitive to infrared and ultraviolet radiation when contained in the little shipping bags. Floating and acclimation with lights on may kill your Berghia. When cleaning lights, equipment and reflectors, it is important to clean salt spray and salt bridges off and NOT wash or drop it back into the tank. Small traces of aluminum and cadmium ions that could be contained in the salt spray crystals can be harmful to delicate life in a coral reef tank. Like corals, invertebrates and some fish, Berghia may be sensitive to overdoses of kalkwasser or overdoses of some additives. Dosing in moderation is best if additives are used. You must also have enough Berghia to fit the task in your tank. Algorithms and predators are discussed on this site to help. Our Berghia are tested and proven effective Aiptasia anemone hunters prior to shipping.

The Trouble with Syringes and Pump Parts: The trouble with the syringe method and injecting Aiptasia is that it does not ever kill the basal cells nor the spawn gametes. Berghia are discrete, target predators and the only way to prevent the release of the Aiptasia Larval Planulae while removing the Aiptasia. We have an in depth study of the Aiptasia anatomy to help us understand this capacity of mass reproduction under stress. It is impossible to “glue” the mouth closed or seal it with anything since the Aiptasia is covered with a protective slime. It would be futile to try anyway because the Aiptasia anemone has so many large stoma on the stalk and tentacles to exchange water, nutrients and defenses with its surroundings. Planula larvae of the Aiptasia are always released when the anemone is attacked chemically by the reef keeper or an indiscrete predator such as a fish or shrimp. We have pictures of the planula larvae inside the Aiptasia clustered together along the Acontia that functions as the release mechanism. There is one exception with the fish but the fish is still an incomplete solution. The Aiptasia’s basal cells split continuously and when the Aiptasia is injected there is a dozen or many more Aiptasia from the basal cells to take that one’s place that got the injection. Pictures of the Basal Cell reproduction are on this web site. Sometimes as many as half of those basal cells let go and populate other areas of your tank and you cannot see them for some time, sometimes for almost a year. They take hold, get rooted in a little hole where they are safe and start to grow. They go unnoticed completely until all of a sudden there is an aiptasia bloom in the tank. Release of the larval planulae produce such tiny Aiptasia they are impossible to see in the tank for an extremely long time. This can mean disaster for corals but is so far removed in time that the disaster is not connected to the attack on the Aiptasia. This can leave reef keepers questioning all their parameters and testing only to find everything within limits. It happens many times but is just not worth the risk, so, if you are thinking about getting Berghia for a tank that is not out of control yet and the current method of control is by injection, then by all means get some Berghia going on that tank while they are still under control. If it is a nano tank, more than likely, after a month or so in a nano you will see the Berghia again and can capture them to move them to another tank if they have completed their job. Aiptasia also spawn under extreme stress conditions and under good water quality conditions and those cells go unnoticed for as much as a year at times. If conditions are right, they too can explode overnight into a mess. More than likely why some people have difficulty getting rid of Aiptasia in their main reef. Some information about that is in the scientific notes on our site in “Learn About Aiptasia To Kill Them”. Basically aiptasia anemones and cells are a super-life and all others not nearly as prolific as they are. Aiptasia cells that lay dormant can outlast a Berghia attack too and those dormant cells buried in the rocks could return at some later date. A total pain for reef keepers until the entire situation is brought under control. What we hope for is the introduction of Berghia at the correct time to get all of the mess cleaned up, but, those little tiny cells can be a problem if they are buried in a place or crack where Berghia don’t go or can’t get to for some reason. Powerhead casings where the seams and brackets are and tubing are places where Aiptasia cells can hide so regular complete cleaning of those and all pump parts will help eliminate that spot and keep the Aiptasia cells from repopulating your tank. A way to inoculate your tank with new aiptasia is to get some macro from a supplier or local reefer who has no idea there are aiptasia cells buried in the middle of the macro. Then you start all over again. Due to the prolific nature of Aiptasia cells and their ability to lay dormant, it could be necessary to add Berghia to a tank more than once. Each time a tank is reinoculated, Berghia may be needed again if the original colony is not still present. If available, quarantine tanks, even for macro algae, help prevent new Aiptasia from getting into the display tank. Even when the best hygiene is practiced, due to the dynamics of life in the reef and the ability of Aiptasia to survive, it is possible additional applications of Berghia will be required to complete the solution. Berghia, when acclimated and applied with care, thought and patience, will control Aiptasia.

Your Berghia Shipment: Our Berghia nudibranch sea slugs are shipped in an ultra high grade clean saltwater at salinity of about 35.0ppt (sg 1.025 +/-1). It is possible to notice an odd aroma after opening the shipping bags even though the water is a very high grade artificial salt mixture. This is evidence of the nudibranchs biology and foul taste to small fish. They definitely can exhibit a scent unique for these nudibranchs. Many reef keepers put some of this water directly into their reefs and no harm comes to their corals or fish, but we recommend a complete replacement of the shipping water with fresh tank water during this acclimatization process prior to placement into the reef. The nudibranch is easy to acclimate to your reef however you should acclimate carefully and shipping water should be discarded as a matter of good practice. The young adult nudibranchs are normally 12mm to a slight bit more (approximately 1/2 inch little slugs) when they are caught from the system for you. Actually they could be more than 1/2 inch but they expand and contract greatly during the day so size is difficult to observe accurately. Their ability to expand and contract during the day is extreme. Much of their bodies are very similar to their prey as they are only a couple of cells thick and like little bags of water. Not considering their Cerata, their bodies expand and contract, very similar to a worm in diameter and appearance. This ability makes it possible for them to escape injury by fast moving invertebrates and to get in where the Aiptasia are rooted to remove all pieces of the Aiptasia’s basal cells preventing reinfestation. In addition to their bodies, many develop long thread-like tails to help secure them to the rocks in swift currents. They are selected when actively hunting as this is the only time when true size can be measured. They expel water when shipped and will curl up tight appearing extremely tiny in the bags. They are guaranteed healthy and will reinflate back to their true size over the next 24 hours. The bag is sealed for safety and transporting.

Important: Turn lights OFF in tank you select to float bags in. (Powerful reef tank or refugium lights will quickly overheat the little bags and toast the Berghia to death.)

Float the bag to bring it to temperature in your reef, sump or refugium.

Then cut the top of the bag off.

Pour a little water from your tank in the bag, wait 5 minutes, then pour in a little more. Repeat until the bag is full, empty the bag and fill again with small amounts each time.

Do this 3x before preparing to put them into the tank. If you drip acclimate, be careful to drip slowly enough. This should take from 1 to 2 hours. They are normally easy to acclimate and you will have no trouble keeping them at home reef tank salinity (approx. between 1.023 and 1.027, dKh 8 to 14, pH 8.1 to 8.4). They can go more or less providing you double the acclimation time.

They should not be touched with your bare hands as they can be easily damaged and may not fare well if they are touched.

Shut ALL power heads off while you insert them into your reef!

DO NOT JUST DROP THEM INTO YOUR TANK!

Let them crawl out on their own or use the spoon method below.

Read these instructions all the way through and plan ahead so this is enjoyable and to prevent injury to the Berghia.

Consider keeping them in a clean, vented, small disposable food storage container, specimen container or jar, away from hot lights (so they don’t get cooked), clipped to the lip of the refugium or tank, until late evening time, after wrasses have gone to sleep in the sand. Berghia are naturally nocturnal and will be more active after sunset. It is not necessary, but, when possible, evening time is a good time to introduce them into your system.

Select a clean, sheltered location, under a coral and near a group of Aiptasia, high on your reef to start the colony. High places are far away from detrivore nests and high rocks are excellent choices to start a new Berghia colony. Bristle worm nests or other detrivore nests may be found in or under low rocks or rocks coated in sediment. A bottom rock can be a detrivore nesting area or Bristle Worm nesting area. These kinds of bottom rocks can be very dangerous and may be hazardous to the nudibranch because the worms are very aggressive in their nesting area. These low rocks or some rocks directly on the sand bed can be poor locations to place delicate, sensitive new additions into the reef environment and this includes the Berghia. Large aggressive colonies of hungry Bristle Worms will consume nudibranch egg ribbons. Even though they are not direct Berghia predators, some will feel they are because of this opportunistic, competitive behavior near the worm nest. All of these potential situations can be avoided by simply placing your Berghia colony up high toward the top in the reef.

Please read this entire web site. Correct information about using Berghia is important to ensure success in your tank. Even in tanks that are overrun with Aiptasia, our Berghia verrucicornis (Aeolidiella berghia stephanieae) will take care of your Aiptasia issue when correctly applied to the situation.

When They Arrive: When they first arrive and the specially selected or made packaging is taken out of the little box, the first thing will be the reaction that these redefine the word “small”. Then think about the importance of this investment to your highly prized reef. The first ones for us cost twice as much as what we sell them for here. We would actually have paid more just to get them because we knew they would work and our first tank was worth it. All things considered, it’s worth taking the time to acclimatize them and insert them into the reef without injuring them. Berghia are very small bodied animals and with water expelled during shipping will appear even smaller than normal. Occasionally healthy Berghia may appear to “float” because they are so light they can crawl on the underside of the water surface tension. These Berghia are well fed and well fed Berghia at this age like to mate. If the bag is a Trio-Pak, you may only see what appears to be 2 little tiny rolled up fuzz balls in the bag. Rock the bag before unrolling the top to be sure one is not caught in the upper corners of the bag. Since they like to mate, they are often mating in the bag and 2 can look like 1. Observe them for a while, they are all in the bag. If they are fully engaged in mating, do not try to force them apart or damage can occur. Allow them to work it out on their own. The Trio-Pak bags are special bags that can stand on their own and not trap the Berghia in the corners. They are small and partially masked, so please be prepared to handle a small bag with a small opening that is slightly difficult to see into. Other bags are specially made and modified here to keep the Berghia healthy during shipping. One may be included with your order for easier float acclimating if you tell us ahead of time. In that case, rock the Trio-Pak to dislodge the Berghia, unroll the top, cut the top off and gently dump the Berghia into the optional float acclimation bag. We use smaller sized disposable food containers and small clear totes to move them here and this may work better than a bag in some cases. Please choose the bag or container style that works best for you to acclimate and handle your Berghia. Trio-Paks can be kept in their original bag for the entire process if handling a small bag that will stand up on its own like a cup will work for you. Group and lot orders may be packed in all clear bags that are specially modified here to maintain the Berghia in good health. Either way they are not giant fish bags to keep shipping costs down but the main reason is to provide a secure healthy package that serves the Berghia needs best. Our Berghia survived a shipping accident in the summer of 2005 and were returned alive to us after 7 days in our special packaging. Their needs are met by our bags but this can make acclimation challenging for some reefers. Being prepared with small containers and small bags of different shape and/or size, plastic pipettes and scissors to cut the bags open and the tips off a pipette if that works for you better. Using a pipette is not necessarily recommended unless this kind of thing is done every day. Practicing a couple times with just water in the pipette to get the technique down is helpful. The water can all drip out before you are ready if the technique is not coordinated. (2ml pipettes used to measure and dose some tank additives are way too small of an inside diameter. Do not use one that’s been used to dose iodine, coral dips, remedies or soap products. Be sure it’s clean, free from contaminates other than a few fresh drops of tank water if a pipette is used.) Use the pipette to blow a stream of water under the Berghia to dislodge it from the bag before using a pipette to pick it up and be sure the opening is large enough. A correctly sized pipette is shipped with your order. If the Berghia is hanging on tight and this is not done right, it’s possible to suck a number of the cerata right off their bodies. They are not so delicate once in the reef where they belong so there is no sense in adding much of this to shipping stress if it can be avoided. Be careful when transferring. The pipette can be slightly pumped to get them out in a safe place on a rock so long as you are agile enough and the Berghia doesn’t attach to the inside of the pipette. If that happens, it’s a little more tricky to get them out. Think it all the way through so this experience is enjoyable.

Shut ALL power heads off while you insert them into your reef! Berghia are nearly weightless so getting them under the water surface is the first step to think through. Use a plastic spoon and get them to crawl on, lift from the bag and put down near the rocks where aiptasia are. (NOT on the sand bed) Berghia are very light and if they were on the sand could be swept into the water column by the slightest current swirl or rising Nassarius snail so they normally will not look for cover on the sand. Aiptasia normally don’t reside on sand beds either and Berghia instinctively know this. You can also use a pipette as mentioned in the previous paragraph, with a large enough opening or invent some method of your own, just take your time and don’t slide or roll them. Be gentle so you don’t knock off a lot of their cerata. Once you have one on the spoon, if you roll the Berghia with the spoon, they shed the cerata appendages like a porcupine. It’s their protection. However, if you do knock a few off, they will grow back. Introduce them high up in the reef and at the opposite end from your overflow. Put ALL of them in one place in each tank that you purchased some for. A synergistic effect is realized in the colonies, so they should not be scattered about randomly. The best place is far away from your overflow and on a rock near a dark spot where they can be in the shade and hide in the rock or under a coral. Normally Berghia will not go over the overflow because they do hang on very well. If you use a rock right against the overflow to establish the colony, then one may wander while searching for aiptasia or the eggs may hatch and too many larvae will go over the overflow. It’s best to establish the first colony away from the overflow, high up in the rocks as possible and under a protecting, shading coral. Since they work best in colonies, the faster results will be had by keeping the entire group together. Even this way, you must have patience. When placing in tank be sure you do not go through the same motions as when feeding the fish to avoid a feeding frenzy with the fish. A tang in motion will just swallow this before it realizes they sting and you will lose the Berghia if that happens. DO NOT JUST DROP THEM INTO YOUR TANK! Many fish will pick them up and spit them out several times until they get a good sting on the lips. When Berghia are rolled up and agitated like that and sting, they will shed their cerata appendages to keep stinging the attacker and distract it so they can get away. However, your Berghia may get injured in the process beyond repair. Some fish that just gulp food down at feeding time like large tangs, may just swallow the Berghia thinking it’s food. A little extra care is prudent to ensure their success considering their rarity and cost. If you happen to accidentally drop a Berghia into an aiptasia, don’t worry about it. It has been reported that aiptasia eat Berghia, but, this is simply just not true from what we have seen for the 12mm ones and larger. Even if it looks like they were engulfed by the aiptasia, the Berghia will work it out and get away, shake it off then sometimes turn around within a minute and eat the Aiptasia that stung it. Just in case we wouldn’t do it on purpose unless you have a Berghia to spare and want to watch the show. Don’t use a huge aiptasia because sheer size may win on occasion. We’ve dropped more than one into an aiptasia and worried over it because of false reports that aiptasia eat nudibranchs. It’s just simply not an absolute fact, at least once the Berghia get to the size of these egg laying young. (Perhaps that author was referring to smaller young between one millimeter to up to 10mm but he doesn’t refer to the Berghia size in the claim.) Perhaps it could happen, we’ve just not been able to duplicate it in any case. If you do want to try it for the show, keep just 1 nudibranch in a small jar for a couple days and feed it well to be sure it’s fully recovered from shipping stress. For the Berghia in your tank, once they have a good hold and are crawling around, be sure the rock where you placed them is not in the blast area of a power head. If so, leave that power head off or reposition it. When the Berghia are well attached to a rock and crawling, it should be safe to turn power heads back on one at a time. Once crawling on the rocks comfortably in the tank, they should be safe. Authors claiming to know all about nudibranchs say that there are not any predators of the Berghia nudibranch but this is an oversight by these authors. Nudibranchs have several predators and this is referred to here and in articles throughout our site. They could also get stepped on or dozed over by something like a large turbo, but, such things are accidental and not predatory in nature. Agile young Berghia are quite capable of slipping away into a small depression in the rock or even in the crack between a couple pieces of bubble algae by deflating a little. They will come out after dark to kill some aiptasia.

When Berghia are shipped they expel water much like their aiptasia prey, so they will appear much smaller than you have ever imagined and will be all white or nearly white colored. This is completely normal. We cannot stress size changes enough so you are not in shock over how small they are at first look. They are very, very small animals anyway, even though full grown they do gain a lot of weight by comparison. Full grown adult Berghia can get up to 34 mm or perhaps a slight bit more (1 1/4 inches). This species of Berghia, common name popular in the aquarium trade is Berghia Stephanieae and correct scientific name as of 2005, Aeolidiella stephanieae does not get to be 2 inches long. This has been copied from an incorrect reference for this species and refers to a completely different species of nudibranch. After looking each day at these delicate appearing nudibranchs, it may look as if a large adult is 2 inches by comparison, but the true species does not grow to such a size. These nudibranchs do not get nearly as large as the full grown adult wild caught Lettuce Slugs that we’ve often seen. Very large, old adult Berghia are not as effective as the young ones in your tank. It takes numerous Aiptasia to grow your Berghia large and our young adults are very active nudibranchs in their quest to consume Aiptasia. With the young adults, all the eggs and activity of their growth spurts in your tank will benefit your system. As you begin acclimation, your Berghia will start to reinflate, then when you put them into your tank they will inflate even more. It may take them a few hours or up to the next day to inflate back to a larger size. Over the next day they should reinflate to their normal size of about 12mm or more. These Berghia hatched a couple of months ago and most people cannot see them when they hatch due to their microscopic size. Since you’ve read this then you should be prepared because these animals are not full grown and are VERY small considering the amount of aiptasia they eat. They will inflate and deflate to get through narrow places or when they are sleeping. Often they sleep curled up in a little tight ball, making full use of their protective stinging cerata. They look like a little ball of quills when they are at rest. Their ability to inflate and deflate helps them hide as well as get into all the tight places aiptasia take hold. (The following jar method is not recommended for more than one Berghia or for the long term. Keeping Berghia in a jar has a 99% failure rate for most reef keepers because micro-mini marine ecosystems are extremely difficult to manage.) If you want to have some fun, keep just 1 of them in something like a rubbermaid or mason jar or any 4 inch jar (like jars Kent activated carbon comes in) with about a couple inches of water from your reef. Leave the top completely off the jar. (Rinse the jar then rinse with tank water to be sure it’s contaminate free.) Refill with fresh tank water and put a Berghia in the jar. Then pull some aiptasia off the rock with forceps and feed a couple to the Berghia. You will enjoy watching them locate the food and eat. Just dump the water every day and replace it with fresh. Keep this container floating in your refugium (to maintain temp and a photoperiod of 12 to 14 hours) and ensure it won’t tip over. You can do this for a week and watch 1 because once in your reef, they will disappear into your rocks soon after you turn them loose. You don’t have to do this but it would be fun to watch. Put a little algae in this container to keep it sweet. A little hair algae works as will some of the others. If you use some dense algae, pull it apart some so you can see into it. The Berghia will try to hide in there. Once in your tank it takes a little while to establish the colony. It may be as much as 3 months before you start to see results. This is not true for everyone, but it depends on how many little aiptasia starts there are to keep them busy. Little by little you will see less and less aiptasia. Just let it work and as with all reef events, be patient. Your aiptasia population may just simply overwhelm the number you have, you might want to get some more to supplement the original small colony. Fertile eggs hatch in about 12 days and your Berghia are laying fertile eggs now. Babies are very tiny so it can take near 3 to 4 months to realize some results if you have a very dense population of aiptasia. In tanks that are out of control and overrun with Aiptasia, this can take from 6 to 12 months. The Aiptasia may appear to bloom after addition of a small Berghia colony as they will move upward toward the top of the rocks. In cases like this, if after 4 to 6 months progress is not being made fast enough, it may be prudent to consider adding reinforcements to your original Berghia colony to make the colony larger. Larger colonies can achieve the positive synergy sooner and this is necessary to gain control over a massive Aiptasia growth or explosion. The Berghia will work, simply maintain water quality and regular maintenance for a healthy tank and as in all marine tanks, have patience.

These are young Berghia at least 12mm long unless you ordered another offered size. They are laying eggs and normally lay from 100 to 250 eggs in a coil at this age. They are very good hunters and very active at this age too.

Where did the Berghia go? They go down under and work from the bottom of a rock upwards. You simply must leave the tank alone and not create rock slides or move things around all the time after adding the Berghia. Moving rocks and creating rock slides will dislodge egg strands and may bury or injure the Berghia hanging out on the dark side of the rocks. It is normal to not see them after the first day or so. They may show themselves again after about a month if you look at first light or after the sun sets. Look and look, they are masters at camouflage so you can stare right at one and still not see it.

How Long Do Berghia Live? Every one eventually wants to know and facts are important in this case. Published information on the internet and in articles amounts to theories as far as we can determine. We track the dates on all of our Berghia including when the eggs were laid, when they hatch and know exactly how old they are. We recently recovered adult Berghia from a tank where 2 of our Trio Paks were used. They were placed into a 100 gallon reef in March of 2008 and we removed them from the rocks in September 2008. They were 2 months old when placed into the tank so this means they were 8 months old when we caught them. We caught both very beautiful adults and their young from a few rocks in this 100 gallon tank. The adults, well over an inch long now and laying lots of eggs are eating lots of Aiptasia and are very active. It appears they will live at least a year and contradicts the 6 month theory that has been published on many web sites and in many articles. We track the age of our nudibranchs and have been recording their lives longer than 9 months for years now. After that they go to reef tanks so we have not tracked them all the way out but we know they live much longer than the original guesses. It is always best not to guess and base articles on facts rather than theory. We do have a unique technique, practice selective breeding and only ship healthy stock. We are certain our healthy stock and outstanding shipping practices contributes to our Berghia’s longer life span. Pictures and a case study of this reef tank located in San Antonio to follow. BTW: The reef keeper did not know the Berghia were still in his tank and they are huge!

How long will it take? I have a 125 six feet long. It was loaded with aiptasia between many small rocks and under shells, inside corals, etc. I put 8 in the 125 and 3 in the refugium. In 4 months there was only 3 large aiptasia left and one little one that I could find. Over the next few weeks, those disappeared completely. I also had aiptasia in the sump and the Berghia babies got there as well. The sump is also clean now, in about 8 months. Basically this equates to closer to a year than just a few simple weeks. Patience is necessary. A picture of that tank is on this site and it does combine two natural predators. The CBB takes smaller Aiptasia from the exposed rocks but was not a complete solution to a coral tank with corals grown together. A CBB cannot get down under so it is never a complete solution like the nudibranch is and that eventually spelled disaster for this tank. We’re very thankful for the Berghia nudibranch in this case.

Do not try to keep them with Peppermint or Camel Shrimp. These Lysmata species eat or shred nearly everything that lives and we are very sure Berghia will be no exception. Some people have no trouble with them, but that depends on the tank and its inhabitants. Peppermints may be safe with leather corals and adult Peppermint shrimp will shred Aiptasia to pieces as well as anything similar in structure. They can eventually kill Tubastrea and small BTA’s that cannot tolerate a tentacle being plucked each night as well as other things. There is an occasional one kept alone that can be fed and kept under control, but, it is not a safe thing to try as they can go after something without warning. Keeping these shrimp safely with Berghia requires the reef to be built up as opposed to flat, providing adequate environment and that the reef be well fed. Peppermints are nocturnal and very shy and this means witnessing the damage they do is not going to happen. Very often zoanthids and polyps will really extend once the Peppermint shrimp are removed if they are in a tank. Peppermint shrimp are easily caught along rocky jetties of the lower Texas and Florida coast, not from reef areas. They are not “reef safe” as some people seem to think. The sting of the Berghia would not even faze these predator shrimp. Cleaner Shrimp are okay as they do not bother the Berghia nudibranchs at all. Old literature says there are no documented predators of the Berghia nudibranchs but we have found this is not correct.

Other Invertebrate and Fish Predators: Sometimes people will keep large predator scavenger animals in their reefs that really don’t belong in there just due to their mere relative size compared to the size of the tank environment. Extra large bottom scavengers that stay within their niche should not pose any competition or annoyance for the Berghia so long as they do stay in that niche most of the time. Sand sifter stars that normally are in the sand bed may climb the glass on occasion. Even though they are not in their niche climbing the glass, they should not pose any problem for the Berghia while clowning around for your entertainment. Occasionally live rock will contain medium and larger comb jellyfish. If the tentacles of a large comb jelly got tangled around a Berghia nudibranch, the nudibranch may lose a number of its cerata. It certainly can’t be considered a very good thing as compatibility goes in the small confines of a tank. We have not tested these nudibranchs in tanks with large comb jellies directly although at least one of our customers does have a medium size comb jelly and has not reported any problems to their nudibranchs. Larger species of fish of several species that pick at life on rocks are very likely to eat a nudibranch and it is likely to be the reason the nudibranch is primarily nocturnal. One fish recently reported to eat the Montipora nudibranch (looks exactly like a small Berghia) is the Radiant Wrasse (Halichoeres iridis). This wrasse may also eat Berghia if the Berghia are exposed. The fish hunts during the day time hours and Berghia hunt at night. Using the nocturnal Berghia nudibranchs in such a tank may take a lot of thought and some skill to ensure success especially when first inserting them into the system. In addition to Peppermint Shrimp, other invertebrates that may harm or negatively impact Berghia nudibranchs include large brittle stars and large predator crabs possibly including the species of Sally Lightfoot that gets as large as your hand. There is also a small worm that thrives in some live rock that eats Berghia larvae. Some fish and invertebrates that feed on the rocks can keep these under control. Having enough Berghia for sufficient eggs is required for some to survive in this case. Good tank mates generally include micro and small star species, Cleaner Shrimp and all the small reef safe crabs and ornamental shrimp species we normally keep in a community reef. They should be okay with Berghia nudibranchs.

Using Kalk or Juice (or other) with Berghia: This is definitely NOT recommended, but a strategy to rescue a coral may be necessary in some cases. As the Berghia reproduce the little microscopic larvae can be anywhere. Taking things into your own hands at this point can mean you kill some Berghia. The older Berghia are expecting to eat aiptasia not some animal that has a significantly altered pH or chemical content. However, on occasion it is necessary to take drastic action to save a coral. If you do have a very large aiptasia that’s stinging something of value, then use forceps to quickly grab the stalk of the aiptasia and snip off the tentacle ring. If this proves to be inadequate, an injection of boiling R/O water will knock it down temporarily. Be careful not to get the slime or white threads the Aiptasia ejects on the threatened coral. Those white thread-like appearing pieces are 100% stinging cells and will burn the coral. Also released are thousands of Larval Planulae that are ejected by the acontial elements that release the white thread-like structures. Boiling R/O water injections or clipping will hold the Aiptasia back for a week or more perhaps and even if that does make it send out some lacerates at the base or spawn, you have Berghia in there and they are quite capable of handling all the aiptasia offspring and spawns in the course of time.

What happens if and when all the aiptasia are gone? You go to dinner and celebrate a natural predator and that your reef is aiptasia free! The colony will disappear naturally over time. They can exist for a very long time in a reef tank when the aiptasia population dwindles. In very robust systems, they may reduce the colony size as the aiptasia decrease and increase again if or when the aiptasia increase. This can happen but, they can also eradicate all the aiptasia and then not exist in high enough numbers to find each other and mate again. Each closed system is different. It is quite likely if you get aiptasia again from somewhere, you will need a booster for the colony to get the Berghia population back up again. You can do this by adding a few more Berghia, if necessary.

Remember: There are occasional exceptions to rules of behavior in the animals we keep in our tanks. This is a dynamic hobby and there are animals that develop strange behavior patterns in some tanks. Normally, given the time, and adequate size to the Berghia colony, the Berghia nudibranchs can take care of all the Aiptasia in a tank when they are applied correctly. But, since there are no absolutes in this hobby regarding other animals, this can work for you in aiptasia control or against you and your nudibranchs. Please observe closely and take time to make accurate assessments if there is something that needs modified to help your Berghia to control the Aiptasia in your tank. We want you to be very successful so questions are welcome any time.