Maintaining a saltwater aquarium is not an easy task. It requires countless hours of balancing and measuring and, of course, selecting the appropriate species to introduce. The goal is to establish a harmonious environment without the negative impact of undesired pests, such as the Aiptasia Anemones, also known as Glass Anemones.
Anyone who possesses a saltwater tank will probably, at one point or another, experience an invasion of Aiptasia. These anemones can become quite hazardous to the flora and fauna in the tank and can cause high stress for the coral and can potentially kill fish as well. They are quite difficult to remove once they have been introduced to the environment, typically as hitchhikers on liverock. It is not uncommon for attempted physical removal to cause an increase in Aiptasia population. Therefore, Berghia Nudibranchs have become a popular means of extricating the pests due to their ability to target only the anemones instead of the rest of the tank, ensuring Aiptasia removal.
The Aiptasia Anemone
In order to better understand the means by which the pest can be destroyed, it is essential to comprehend what the anemone is and what its characteristics consist of.
Aiptasia can be quite misleading due to its elegant nature. Despite its beautiful appearance, it is an aggressive and invasive creature that is capable of overrunning an entire aquarium. When the anemone is disturbed by another animal, it ejects a series of stinging strands that contain nematocysts, which consist of venomous cells that can damage or even kill aquarium fauna.
Aiptasia is a type of symbiotic cnidarians that belongs to the Anthozoa class which contains sea anemones as well as corals. This particular sea anemone is found mostly in tropical waters and, more specifically, on the roots of mangroves or in nearby substrates.
This sea anemone maintains a symbiotic relationship with dinoflagellates, or algae, as do many other species of cnidarians. These symbionts provide the Aiptasia with food which primarily consists of sugars and lipids that are produced as a result of photosynthesis. In return, Aiptasia provides the dinoflagellates with inorganic nutrients as well as a protected environment.
The Aiptasia species consists of “weed-like” anemones that are capable of surviving in a number of environments that vary in saline concentrations as well as other water parameters. It is for this reason, combined with the fact that the species is able to reproduce very rapidly, that Aiptasia has become one of the most bothersome pests in saltwater aquariums.
Despite their undesirability in tanks, their fast reproductive processes and resiliency has made them excellent objects of study in laboratories. Because of this, Aiptasia has become the source of much knowledge in regards to the biology of cnidarians, particularly in regards to symbiotic relationships between algae and cnidarians. Symbiosis is an integral phenomenon to the survival of ecosystems containing corals. Without the algal symbionts that can be destroyed when coral bleaching occurs during periods of stress, coral reefs can experience devastating effects.
Species of cnidarians are able to have two different forms, this being the medusa or the polyp. Aiptasia, along with all other anthozoans, exist in the polyp form. The body of the anemone consists of a pedal disc which the organism uses to attach to the substrate on which it resides. The column of the body is elongated and smooth and the mouth consists of a disc from which stinging tentacles protrude.
Unfortunately for saltwater aquarium owners, Aiptasia is able to reproduce both asexually and sexually. The asexual reproduction of Aiptasia consists of a process known as pedal laceration. This indicates that groups of cells are able to be torn or pinched off the pedal disk which is located on the base of the anemone’s central column. These pieces develop into buds and, within two weeks or less, are able to use their new tentacles and mouth to consume their own food. These clones are able to spread to other areas of the tank in order to colonize another location. These animals are also resistant to one another, meaning that one anemone will not attack any of its clones.
In contrast to other species of cnidarians, Aiptasia can regenerate or generate a whole animal from a simple single cell. This makes physical removal of the pest an enormous challenge. Asexual reproduction is believed to increase when the animal is under large amounts of stress particularly when oxygen is low, when circulation is disturbed, in periods of low lighting, or when under attack by predators or by those trying to physically or chemically remove the anemone.
Although asexual reproduction is probably more common, sexual reproduction may occur as well. The creatures, which consist of two separate sexes, are able to produce free swimming zygotes via external fertilization which eventually becomes a polyp after it settles in a particular location of the tank. Both the male and the female Aiptasia release their gametes with fertilization occurring in the surrounding water. The zygotes are referred to as planula larva that are able to swim but eventually settle in one location where they undergo metamorphosis. It is then that the Aiptasia takes on its adult polyp form. There is also some debate as to whether or not fertilization may occur internally. The newly generated larva do not possess symbionts. It is not until they have matured into polyp form that they are able to acquire symbiotic dinoflagellates from the environment.
Aiptasia Tank Introduction
The majority of tank owners consider the anemone to be a pest, which most often enters the tank on coral or liverock. They are usually far too small to see at this point. However, in no time at all, the Aiptasia is able to spread and take over the whole tank. If there is nothing done to control the growth of the pest, it can pose an enormous risk to the other creatures in the tank, including coral, invertebrates, and fish.
Ways to Control Aiptasia
There are several chemical solutions that are available in order to eliminate Aiptasia. Although they may be effective, they typically contain harmful or toxic substances that can change the chemistry of the tank and even kill other species in the tank.
Other solutions consist of natural predators such as the Copperband butterfly fish, the filefish, and the Peppermint shrimp. Although these fish may attack the Aiptasia, they are usually not safe for reefs and are likely to feed on polyps, sea mats, corals, clams, and other invertebrates. Additionally, these animals are known to browse on Aiptasia but none of them actually consume the anemone as a primary source of food. This means that the anemone will not be fully eradicated from the saltwater tank.
It can be very disheartening when you find Aiptasia within a tank since they are so difficult to remove. However, there are numerous available solutions for getting rid of Aiptasia although there is certainly one which has been shown to be the most effective – the Berghia Nudibranch.
Benefits of the Berghia Nudibranch
Fortunately for the aquarium owner, nature has given us the perfect solution to the problem. The primary benefit of this creature is that it feeds only on the Aiptasia, making it safe to the rest of the aquarium. Aiptasia does not rely upon light to exist and can therefore live within the crags of rocks and corals. Therefore, the Berghia is quite beneficial as it is very small in size. This means that they are able to crawl within the crags of the coral and underneath rocks without harming the rock or coral. They are also known for consuming all of the anemone, leaving nothing to regrow. And, due to their small size, they do not add bioload to the tank or affect the quality of the water.
Berghia is able to reproduce quite quickly within the tank due to their hermaphroditic nature. Each of the mature creatures is able to mate and lay their eggs each day. The only limiting factor to Berghia reproduction is water quality and the availability of the Aiptasia Anemone on which the creature solely feeds.
Bergia Nudibranch possesses sensory organs known as rhinophores that are able to use chemicals in order to detect the location of the Aiptasia. This means that the creature is able to eradicate the anemone, even when the Aiptasia is too small to be seen by the naked eye.
The Aiptasia eaters are better able to consume the anemone successfully as they have evolved a strategy by which the Aiptasia can be approached without feeling endangered. This therefore prevents the release of the stinging strands or nematocysts and larva, meaning that no new Aiptasia Anemone can be generated.
Berghia is also harmless to the invertebrates and fish in the tank and they do not compete for either food and space. They are also nocturnal, meaning that they will not negatively affect the aesthetics of the tank during the day.
What to Expect After the Introduction of Berghia
For each 100 gallons of water, it is recommended that 8 Berghia be added in order to eliminate a moderate to severe Aiptasia problem. If there are only a few Aiptasia present in the tank, Berghia is not recommended as the creature may starve due to insufficient Aiptasia population.
Berghia, which are a type of sea slug, require the appropriate environment in order to survive and thrive. Keep in mind that there are some areas where the Berghia may not be able to get. For example, Aiptasia is able to enter tubing, power-heads, and sumps where the Berghis will not be able to follow. Therefore, these areas will need to be cleaned by you in order to prevent the spread of the anemone.
How Long Does the Berghia Take to Eradicate the Aiptasia Problem?
This depends primarily on the number of Aiptasia in the tank along with the number of Berghia which have been introduced into the environment. It should be expected that 8 Berghia per 100 gallons of water would take approximately two to three months to completely remove all of the Aiptasia within the tank. It is important to not get discouraged if you do not see any improvement in the tank. It can often take several weeks in order for any difference to be seen in the population of Aiptasia. The Berghia need the opportunity to completely acclimate before they are able to take care of the problem.
Caring for the Berghia
Although there are many species of animals that are considered safe for reefs, this does not always go as expected. Occassionally, these species have been known to be detrimental to saltwater reef tanks. However, the following are a series of species which should generally be avoided in a tank containing Berghia.
You should avoid those species which hunt the area of the liverock during the night such as butterfly fish, filefish, wrasses, and some species of dotty backs. Although it is impossible to completely predict the behavior of fish, nocturnal hunters should be avoided.
Other creatures which have been known to prey upon Berghia are peppermint shrimp and coral banded shrimp which are known to hunt at night for their food as well as crabs such as arrow crabs, Sally lightfoot crabs, pom pom crabs, emerald crabs which have no available algae to consume, and rock crab hitchhikers.
Even Aiptasia has been known to eat the Berghia if the sea slug is placed directly into the mouth of the anemone. Therefore, it is essential to take particular care when the Berghia are being added to the tank.
In short, the Berghia is truly nature’s answer to the question of Aiptasia infestation. As long as the Berghia colony is correctly added and allowed to acclimate to the new environment, the sea slug is well able to bring the Aiptasia population under control and eliminate the pests.
It is essential to keep in mind that these tanks are created to simulate the natural environment and are not natural in themselves. Therefore, it is integral to ensure that the environment is well cared for in order to ensure the health of the flora and fauna within the saltwater tank.
With the proper amount of attention and care along with Aiptasia control, it is possible to enjoy a beautiful tank free of dangerous pests.