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Coral Feeding – Do You Do It???

Corals belong to a group of animals called Cnidarians. The Phylum Cnidaria consists of over 9,000 species of animals which are found exclusively in aquatic environments, and then mostly in marine habitats. Other types of Cnidarians are Jellyfish, Anemones, Sea Pens, and Box Jellies.

The simplest form of a coral is a polyp, which consists of a basal plate that is used to attach the coral, a digestive sac, and a mouth surrounded by tentacles with cnidocytes (or nematocysts) – stinging cells used to catch prey (see below diagram). These polyps reproduce asexually to form colonies of genetically identical individuals. These colonies are what is normally found in the home aquarium and can be extremely varied in both shape and colour, even within the same species of coral.

Diagram of a coral polyp, courtesy of wikipedia

Diagram of a coral polyp, courtesy of wikipedia

Corals, like all other animals, are either herbivorous (plant eating) or carnivorous (animal eating) and prey primarily on plankton (ie those organisms that are too small to swim against the currents and tides). Plankton can be separated into 3 main groups – Zooplankton, which consists of animals like copepods, amphipods, rotifers, and also larval forms of fish, crabs, and other corals; Phytoplankton, which consists of plants and algae like Tetraselmis, Nannochloropsis, Isochrysis; and Bacterioplankton, which consists of those bacteria which are responsible for breaking down organic material.

Some corals also host within their cells a symbiotic (meaning “living together”) algae called Zooxanthellae. This algae is responsible for the primary brown colour attributed to a lot of corals. The more zooxanthellae a coral is hosting, the browner the coral becomes. This relationship is a mutualistic one, meaning that both organisms benefit from the association. The algae receives a fairly safe place to grow and reproduce, with a steady supply of “fertiliser”, while the coral receives a portion of the energy that the algae converts from the surrounding light.

It is this relationship which has led many aquarists into believing that corals only require a decent light for them to obtain the necessary energy to survive. Recent reports and studies have shown however that by providing a range of both phytoplankton and zooplankton to your reefs, not only will corals become more colourful (as they are reducing the zooxanthellae in their tissues and utilising the energy in the food they are hunting on themselves), they will grow faster, be more resilient to disease and predation, and we have also heard reports of corals actually spawning once plankton has been introduced into the home aquarium.

Obviously there is no miracle fix for growing corals. A wide variety of both abiotic and biotic factors influence how healthy corals will be. However if you do plan on keeping corals in your aquarium, you will be amazed at the difference the addition of plankton will have.

There are a variety of readily available plankton specifically designed for reef aquariums. Live zooplankton such as rotifers, copepods, artemia (newly hatched and also ranging through to adults), and amphipods are commonly available. Phytoplankton like Nannochloropsis, Tetraselmis, Isochrysis, Pavlova and Thalassiosira weissflogii are also available in concentrated amounts that are stored in the fridge, making it extremely easy to keep a variety of highly nutritious algae to feed to your animals. Products like Phyto Diet are an accumulation of individual species, allowing a well rounded diet to be easily added to the aquarium. Also products like Coral Diet mimic the zooplankton allowing aquarists to feed their reef without the need for culturing live plankton.

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Sharks on the Endangered Species List

This alarming list was compiled by “Save our Sharks“, i thought the word needed to be out to as many different people as possible so am reposting it here with their permission. Please visit their site and help get the word out on the plight of one of the marine environments awesome animals…

Although it is not well publicised in global media, there are many shark species heading towards extinction.

Without international protection, some will disappear in our lifetimes if destructive fishing methods persist and current population trends continue.

Not listed here – are all those species for which there is not enough information about population numbers to be able to classify them in these categories. For example, the Megamouth Shark is said to be the rarest of all the shark species – it is classed as ‘data deficient’ and does not appear on these lists.

It may well be that there are many more species to be added to these lists – but until more research is conducted we will not know.

Below are those species listed as Vulnerable to Extinction and as Endangered Species by the IUCN, 2008.
Some of these species are very well known. But sadly, are still in danger of extinction.

The Leopard or Zebra shark

The Leopard or Zebra shark

Vulnerable to Extinction – Definition – Considered to be facing a High Risk of extinction in the wild

  • Carcharhinus leiodon (Smoothtooth Blacktip)
  • Carcharhinus longimanus (Oceanic Whitetip Shark)
  • Carcharhinus signatus (Night Shark)
  • Carcharias taurus (Grey Nurse Shark)
  • Carcharodon carcharias (Great White Shark)
  • Centrophorus granulosus (Gulper Shark)
  • Centrophorus squamosus (Nilson’s Deepsea Dogfish)
  • Cetorhinus maximus (Basking Shark)
  • Galeorhinus galeus (Liver-oil Shark)
  • Hemipristis elongatus (Snaggletooth Shark)
  • Hemiscyllium hallstromi (Papuan Epaulette Shark)
  • Hemiscyllium strahani (Hooded Carpet Shark)
  • Lamna nasus (Porbeagle)
  • Nebrius ferrugineus (Tawny Nurse Shark)
  • Negaprion acutidens (Sharptooth Lemon Shark)
  • Oxynotus centrina (Angular Rough Shark)
  • Pseudoginglymostoma brevicaudatum (Shorttail Nurse Shark)
  • Rhincodon typus (Whale Shark)
  • Sphyrna mokarran (Squat-headed Hammerhead Shark)
  • Sphyrna tudes (Smalleye Hammerhead Shark)
  • Squalus acanthias (Piked Dogfish)
  • Squatina albipunctata (Eastern Angel Shark)
  • Stegostoma fasciatum (Leopard Shark)
The Whale Shark

The Whale Shark

Endangered Species – Definition – Considered to be facing a VERY High Risk of extinction in the wild

  • Carcharhinus borneensis (Borneo Shark)
  • Balantiocheilos melanopterus (Silver Shark)
  • Carcharhinus hemiodon (Pondicherry Shark) *Critically Endangered
  • Centrophorus harrissoni (Harrison’s Deepsea Dogfish)
  • Glyphis gangeticus (Ganges Shark)
  • Glyphis garricki (New Guinea River Shark)
  • Glyphis glyphis (Speartooth Shark)
  • Glyphis sp. nov. A (Bizant River Shark)
  • Isogomphodon oxyrhynchus (Daggernose Shark)
  • Squatina aculeata (Sawback Angelshark)
  • Squatina argentina (Argentine Angel Shark)
  • Squatina guggenheim (Spiny Angel Shark)
  • Squatina occulta (Smoothback Angel Shark)
  • Squatina punctata (Angular Angelshark)
  • Squatina squatina (Angel Shark)


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The Benefits of Decapsulating Artemia

One thing I have noticed aver the past 12 months is the increasing popularity people purchasing decapsulated artemia compared to normal artemia. Decapsulated artemia offer a variety of advantages to normal encyted artemia, including an increased hatch rate and a more nutritious newly hatched artemia for your animals to consume. This is due to the fact that the artemia does not have to struggle to hatch out of its hard outer shell (called a “chorion”) therefore uses up less energy and therefore less of its yolk reserves. If you are feeding our newly hatched artemia (less than 24 hours old) then decapsulated artemia eggs are by far the best way to go. Another, possibly lifesaving comparison between the two, is that there are no empty egg shells floating around in your culture chamber once the artemia hatch. These artemia shells can cause increased mortality rates in larval fish if the shells get caught in the mouths and throats of the fish, causing them to starve and subsequently die.

Decapsulating Artemia cysts is a very simple process, one that anyone can do at home. You just need a few household items and to follow a few very simple steps.

What you will need –

  1. Small plastic container (about 500ml)
  2. Liquid Chlorine (pool chlorine works best – available at any pool supply store for about 70c per liter)
  3. Artemia Cysts
  4. 100 micron plankton mesh
  5. Teaspoon
  6. Tapwater (200ml)
  7. Rubber gloves

Methodology

  1. Place about 20g of artemia cysts (approx. 4 heaped tablespoons) into the small plastic container
  2. Add approx. 200ml tap water to the container and use the teaspoon to stir the artemia/water mix thoroughly
  3. Let the eggs hydrate for a minimum of 1 hour and a maximum of 2 hours stirring the water occasionally (every 15 minutes or so). Do not continue with the decapsulation if you hydrate the eggs longer than 2 hours as you will then kill the artemia.
  4. Be sure to read the appropriate MSDS on Chlorine before starting and follow all of the health and safety guidelines. Also ensure that you are wearing rubber gloves when handling chlorine to avoid contact with your skin.
    Once Hydrated, add approx. 200ml of liquid chlorine. Be sure to do this stage in a well ventilated area as the chloring fumes can be noxious.
  5. Stir continuously with the teaspoon. The eggs will change from brown to white, then finally to orange. This is the chlorine dissolving the hard outer shell, or chorion, of the brine shrimp egg. Once 90-95% of the cysts are orange, pour the mix through the 100 micron plankton mesh and rinse thoroughly until there is no trace of chlorine.
  6. Remove excess moisture from the decapsulated eggs and place in a airtight bag or container.
  7. Store refrigerated untill needed. Decapsulated cysts have a normal refrigerated shelf life of 6-8 weeks so be sure to only decapsulate enough to last you for this time period.

Once you have decapsulated your artemia, you can either hatch them out normally to feed to your larval/juvenile fish, grow them out to adults in approximately 3 weeks by feeding them a nutritious algae feed such as tetraselmis or phyto diet, or you can even feed the decapsulated eggs directly to your reef aquarium – both your fish and your invertebrates will love them.

One more thing. If you plan on raising your artemia beyond the 24 hour mark to feed to your aquarium it is vitally important to ensure that the artemia themselves are as nutritious as possible. If your artemia have not been fed recently then they will have an extremely low nutritional profile and be of virtually no benefit to your inhabitants (i normally compare this to eating the shells of an egg compared to eating the egg itself). Ideally feed your artemia to your aquarium approximately 1 hour after you have fed them with the algae concentrates mentioned above. This way they will have full bellies and you will be delivering extremely nutritious algae to your animals. If you are feeding your artemia to larval or juvenile fish, it is also strongly recommended to further enrich the artemia with Highly Unsaturated Fatty Acids (HUFA) similar to what can be found in our Plankton Enrich product. This way you are providing your animals with an extremely nutritious diet which will increase survivability, colouration and growth rates.

If after reading this you are sold on the benefits of decapsulated artemia, but either dont have the time or space to dacapsulate them yourself, you can always buy them already decapsulated from us here.


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Amyloodinium ocellatum – Marine velvet disease

Basic Info
Dinoflagellates are most commonly seen as the organisms present in red tides and even as the cause of Ciguatera poisoning in humans after eating some reef fish. They have dramatic impacts on marine ecology and human economic interests alike. Parasitic dinoflagellates are a diverse group within the phylum Dinoflagellata. Members of the family Oodinidae known to cause disease in both freshwater (Oodinium sp.), and marine fish. Marine velvet disease is caused by a member of the Oodinidae family; Amyloodinium ocellatum.

Amyloodinium ocellatum is the only member of its genus and is a significant disease agent in marine aquaria and also aquaculture. Wild specimens are generally from tropical waters (23°C-27°C) making reef aquaria ideal breeding grounds. The host range of A. ocellatum is particularly broad, being able to infect almost any fish species, some shark species and is even capable of infecting (‘hyperinfecting’) other marine parasites such as gill flukes.

Life-cycle
Three stages are observed in the life-cycle of Amyloodinium ocellatum: the trophont, that attaches to and feeds on fish gill and epithelial tissue; tomont that undergoes division on the substrate; and a free-swimming, infective dinospore. Similarities in the life-cycle can be drawn with Cryptocaryon irritans (Marine white spot) however these parasites are not closely related.

Attachment of the trophont to the host is facilitated by root-like structures called rhizoids. These penetrate the skin and gill cells of the host and serve as an anchor. A tentacular process known as a stomopode is also present in this life-stage. The average maximum size of the trophonts is 100-150µm (Micro meters – A metric unit of length, each micron is equal to one millionth of a meter) with individuals occasionally found up to 350µm.

Amyloodinium ocellatum

Amyloodinium ocellatum

Upon reaching maximum size the tomont retracts its rhizoids and drops from the host to the substrate. There it forms a cyst virtually independent of its external environment. After approximately 12 hours, division begins within the cyst with a maximum of 8 divisions occurring, depending on the initial size of the tomont (usually 5 or 6). Timing of the life-cycle is inversely temperature dependent, the optimum temperature for development is between 23°C and 27°C. At this temperature trophont development can be completed in three days.

Once dividing cells have reached a critical mass, the infective dinospore stage emerges and begins to seek new hosts. How this occurs is not precisely known.

Pathogenicity
The gills are the primary attachment site for A. ocellatum infections, however infections can also occur on skin and eyes. Attachment to the host with rhizoids can cause physical damage to surrounding cells of each trophont. Heavy infestations can lead to gill hyperplasia (increase in the number of cells in the area causing gill lamellae to fuse together), inflammation, hemorrhage (loss of bodily fluids) and necrosis (localised cell death). Damage is thought to be exacerbated by the constant twisting motion of the trophont. Anoxia (lack of oxygen in arterial blood and tissues) is generally regarded as the cause of mortality, in as little as 12 hours in heavy infections.

Life Cycle of Amyloodinium ocellatum

Life Cycle of Amyloodinium ocellatum

Treatments
Treatment of Amyloodinium ocellatum in marine aquaria is fraught with problems. The parasite itself is able to reproduce in salinities ranging from 10ppt up to 45ppt and temperatures from 17°C up to 40°C, making it more resistant to environmental change than most of its hosts. Treatment also becomes problematic when targeting the tomont stage. This is isolated from the environmental conditions by its cyst wall, making it near impervious to chemicals. There are however a number of treatments that are at least partially effective against the parasite.

Substances affecting the trophont stage are generally non-specific chemicals. These include formalin, copper compounds, chloroquine, hydrogen peroxide, and fresh water baths. While these compounds are effective in shocking the parasite from its host they do not generally arrest development and trophonts are able to quickly form a tomont. Many of these substances are also toxic to the fish, making them generally ineffective as control measures. Copper compounds can be useful in dinospore elimination. However, their high toxicity to invertebrates rules their use out in most marine aquaria. Chloroquine, a common human anti-malarial drug, has also been found effective against A. ocellatum by killing the dinospores on excystment. However, it also is highly toxic to invertebrates and micro and macro algae (not to mention extremely hard to find). Five minutes in a freshwater (de-chlorinated) bath will remove most trophonts from an infected fish. This is a useful method of eliminating many external parasites and should be considered as part of a routine quarantine protocol (improper use of freshwater baths can be as detrimental to fish as the parasites themselves- please consult a reputable marine aquarium retailer before you undertake freshwater bathing).

Some substances have been found to act on the tomont stage, these include malachite green, acriflavine, furnance (nifurpirinol) and nitrofurazone. While affecting division of tomonts is useful in controlling infection, these substances are all highly toxic to invertebrates, making them unsuitable for use in most display tanks.

Dinospores have been shown to be susceptible to UV exposure. UV and ozone sterilisation have been proven to be effective in controlling infections in large-scale systems. However, these treatments often will not eliminate infections from a system and are generally very expensive.

Immunity
Fish have been observed to develop strong resistance to infection by A. ocellatum after repeated non-lethal challenges. Dinospore attachment is apparently not affected, however an anti-trophont mechanism has been proposed as the means of resisting infection. Immune fish are able to reject trophonts, or at least severely retard trophont development. Protective response to A. ocellatum can last for up to 6 months in Amphiprion frenatus (Tomato clownfish). It would be unwise to rely on immunity alone to control an outbreak, however. At 25°C it takes approximately 20 days for an immune response to seen in fish. This is ample time for Amyloodinium to kill all your fish twice over.

Recommended Treatment Procedure
If you do not own a quarantine tank then get one. Your local marine retailer should be able to outline the correct quarantine practices you should be undertaking. They are marine aquarists first and best weapon against many disease outbreaks. Due to the size of Amyloodinium ocellatum diagnosis is often difficult without a microscope. Fish that show any signs of disease should be returned to your quarantine tank. The main tank should also be watched closely for any other fish presenting symptoms.

If you decide that treatment is necessary, one method is to perform daily freshwater baths for five minutes over a period of one week to affected fish (always watch fish that you are bathing in freshwater. If they are showing severe stress then cut the bath short and immediately place the fish back in the quarantine tank). After bathing be sure to dispose of the bath contents away from the main and quarantine tanks and sterilise the container (boiling water is the best chemical free way to do this). Make daily water changes to the quarantine tank for the same period, being sure to siphon the bottom (where tomonts will be dividing). Although this may not be totally effective in controlling the parasite it will reduce the severity of infection and allow time for immunity to develop.

Another less stressful method is to consult your local veterinarian for a supply of chloroquine and treat your quarantine tank at 10 milligrams of active quinine per litre, for a minimum of 21 days. Once the treatment has been added to the water, there is no need for re-treatment unless water changes are needed.


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Cryptocaryon irritans – Marine White Spot

BASIC INFO
Cryptocaryon irritans is an external parasite belonging to a group of organisms known as protozoans. These organisms were long thought of as belonging to the kingdom of Animalia, but as the classification of living things has become more detailed, they have now been moved to a separate kingdom called Protoctista. This new kingdom encompasses single celled organisms such as amoebas, dinoflagellates (responsible for causing toxic red tides), slime moulds, ciliates, and certain algae.

C. irritans is also referred to as marine white spot disease, or marine ich from its external similarities to the freshwater white spot parasite lchthyophthirius multifiliis. These two similar parasites are however not related. They are both ciliates (characterized by being covered by cilium, or fine ‘hair-like’ processes that beat in unison to give movement), both have similar life cycles and pathology (development and nature of disease), but have reached these similarities from convergent evolution (Noga, 2000).

C. irritans is one of the most important ‘diseases’ in warm water marine aquarium fish. It has been described as being opportunistic, waiting until the defense mechanism of the fish host is weakened before infestation occurs. This statement, however, fails to reflect the natural relationship the parasite has with the host. Within natural populations, the parasite and host exists in a symbiotic relationship, with most wild fish only having a light infection which has very little impact. Aquarium fish, however, are susceptible to critical outbreaks of the parasite, as the closed aquarium system benefits the parasites high reproduction rate, and allows the parasite to overwhelm the host. There are also reported to be several different ‘strains’ of the parasite and possibly even more than one species of Cryptocaryon (David Vaughan, pers corn, Diamant et al., 1991), which may prove to be increasingly immune to various common treatments and controls utilized in the marine industry today.

Life Cycle of Cryptocaryon irritans

Life Cycle of Cryptocaryon irritans

DIAGNOSIS
Individual fish behavior is the best method for determining problems with disease as this is usually the first sign of upcoming problems. A lack of appetite, increase in respiration, scratching or rubbing on rocks or other equipment, a loss of colour or hiding may lead to closer examination and therefore picking up disease related problems before they are serious.

Even fish with heavy infestations of C. irritans may not show the characteristic white spots of this parasite, as infection sites may differ between individual outbreaks. Gills are usually the preferred site of attachment, increasing the respiratory due to clogging with the parasite, mucus and tissue debris, driving most fish to the surface where the dissolved oxygen levels are usually higher.

Using a torch to ‘backlight’ the fish in a darkened aquarium is the best method to visually inspect whether the fish has an outbreak of C. irritans. Depending on the severity of infection, the fish can either have a few white nodules over its body, or can look like it has a dusting of salt. A loss of colour can occur in the areas surrounding the infection as the parasite destroys the pigment cells of the fish’s epithelium.

As a few different parasites cause similar external characteristics on the host, the most definitive method of diagnosis is by use of a microscope. A scraping of the host’s epithelium showing the ciliated parasite is pathognomonic (characteristic). The ciliate will appear to be spherical to oval shaped, covered with fine ‘hair-like’ cilium, and either moving quite rapidly (infective tomite stage), or slowly rotating in place (mature trophont stage). The mature trophont also has a four lobed nucleus, which is characteristic of C. irritans (Noga, 2000).

Cryptocaryon irritans

Cryptocaryon irritans

TREATMENT
Once the fish has been definitively diagnosed with Cryptocaryon there are a few different methods that can be utilized to eradicate the parasite Treatment should occur as soon as detected as the parasite can reproduce very quickly, infecting other fish within the aquarium.

The infective “theront” stage of the Cryptocaryon lifecycle is quite susceptible to reduced salinity allowing euryhaline (wide salinity range) fish to be treated easily. Decreasing the aquarium salinity to 16 parts per thousand (ppt) or below can halt the spread of the parasite. Keeping the salinity at this level for at least 3 full lifecycles of the parasite (each life cycle being anywhere from 6 – 15 days at 24 degrees Celsius) will help in the removal of most trophonts from the host. Once the salinity is increased to above 20ppt, any remaining trophonts on the fish are able to then resume the lifecycle if conditions within the aquaria favor another outbreak. Many stenohaline (narrow salinity range) fish will tolerate an indefinite salinity of 16ppt. but some may become aggressive or hyperactive. Most invertebrates will not tolerate a significant lowering of salinity for any duration.

Dipping in freshwater to remove the trophont stage from the fish is only usually partially successful. Smaller trophonts can be protected from the osmotic shock of the reduced salinity by being under the epithelium layer and mucus of the fish, therefore only larger trophonts which have grown through the epithelium are lysed by the freshwater. Freshwater dips are also very stressful on the fish and therefore can be counterproductive to treatment.

As Cryptocaryon is pathogenic at temperatures between 20°C and 30°C, lowering the temperature below 19°C will stop reproduction. This method is very unpractical however, and most tropical fish will not tolerate the drop in temperature. If dealing with temperate species, maintaining the aquarium at less than 19°C is a method of control that is least stressful for the inhabitants.

Chemical treatments work by killing one or more stages of a disease’s lifecycle. Many parasites such as Cryptocaryon are very resistant to most chemicals while attached to the host (trophont stage), or undergoing cell division on the aquarium substrate (tomont stage). Luckily the infective theronts (free swimming stage that hunts down the fish host) are susceptible to a number of chemicals (see below) and can be killed quite easily.

Copper has been used historically to treat Cryptocaryon outbreaks, but is not advisable in the author’s opinion for many reasons. Firstly it is an immuno-suppressant and toxic to gill tissue, causing the fish’s usually already decreased immune system to become further reduced. This most likely leads to secondary infections from opportunistic bacteria and viruses that may be living within the aquarium. Secondly copper has a very low therapeutic level, allowing very easy overdosing of the animals. Thirdly, there are a lot of fish that cannot tolerate the levels of copper in the water that is needed to kill the theronts. Species such as sygnathids (seahorses and pipefish), mandarin fish, elasmobranches (sharks and rays), various wrasse, butterfly, and clownfish species, banggai cardinals, and firefish to name a few are considered to be sensitive. All invertebrates (corals, anemones, crabs, snails, sponges etc.) are also considered to be copper sensitive, and will not tolerate any addition of copper to the system. Fourthly, copper can come out of suspension and ‘plate’ objects such as piping, aquarium glass, and pumps. Even once all the copper has been removed, the ‘plated’ object can ‘leach’ copper back into the aquarium, causing mortalities in invertebrates that have been newly added.

Quinine based medication (Chloroquine phosphate and Quinine hydrochloride) have been used with great success to treat Cryptocaryon outbreaks. Quinine is an anti-protozoal drug used mainly in the human treatment of malaria (also a protozoan). The quinine kills the theronts stage of the parasite on excystment from the tomont thus stopping re-infection of new fish. It is non-toxic to most fish at the correct dose rate (5-10mg/l) but it is highly toxic to micro- and macroalgae, and to some invertebrates (anemones, corals etc.). It is also non-toxic to bacteria, therefore not affecting the beneficial aerobic and anaerobic bacteria within the aquariums biological filter. Being a human medication, quinine is relatively expensive, and needs to be purchased through a qualified medical practitioner within Australia (either doctor or vet).

Formalin (which is an aqueous solution of 37 to 40% formaldehyde gas) has been used to treat a variety of fish diseases including protozoal ectoparasites, monogenean worms, and water moulds on eggs with mixed success. It is, however, both volatile and irritating, and has caused cancer in lab rodents. Formalin works by interrupting tomont division and is also lethal to theronts. It also has moderate antibacterial properties thus it inhibits biological filtration. As well as being irritating to the gills, it has algaecidal properties (Schnick, 1973) therefore having the potential to further reduce oxygen levels. Because of this, if formalin treatment is going to be used, it is strongly recommended to heavily aerate the water. Some fish are also susceptible to formalin so levels should be increased slowly and fish behavior observed.

Using herbal remedies such as garlic and onion to treat diseases has become increasingly common. Unfortunately there is no evidence that suggests that these are effective in the treatment of Cryptocaryon and may be even detrimental to the fish’s health if overdosed. Garlic extract – allium satiyum – has however been proven to kill freshwater white spot lchthyophthirius multifiliis at the theront stage after 15 hours, as well as controlling monogenean flatworm infestations, while onion is useful for treating parasitic copepods.

CONCLUSION
Ideally the best method of treatment of any disease is by quarantining and probiotic measures. By quarantining any new fish in a separate aquarium for a minimum of 21 days at 24 degrees (some reports recommend even a 6 week quarantine period) and treating as if they were infected by a suitable proven method of control is the only way to be sure that the fish is free from the parasite. Once they have been introduced into the main aquarium, using probiotics such as spirulina to promote the fishes own immune system is advised. It is also beneficial to enrich foods with essential compounds such as omega 3 oils, lipids, protein and pigments, ensuring that you are providing your fish with the highest nutrition and therefore best possible means of fighting off any infection.


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Coral Reef Nutrition

Eric Borneman contributed an exceptional article on Reef Nutrition and how this correlates to our marine aquariums. The full article can be found in edition 4 of our magazine, but we have an excerpt here from Eric’s work…

“A coral reef supports a tremendous variety of life, all of which are dependent on energy sources for their survival, growth and reproduction.

There are two basic types of organisms in terms of their method of gaining energy: heterotrophs and autotrophs. Most autotrophs are photoautotrophs, also called primary producers; they use sunlight, converting its energy through photosynthesis into energy rich products (reduced forms of carbon, usually in the form of simple sugars) that are used by the organism. In this way, they form the beginning of the food chain, as they are the original or primary source of dietary energy for all other organisms. Photosynthetic bacteria or cyanobacteria, may also be considered to be primary producers, and their biomass on and near coral reefs, including in the water column, is enormous. There are also chemoautotrophs; bacteria that oxidize inorganic compounds such as hydrogen sulfide, ammonium or ferrous iron as an energy source are chemoautotrophs. Heterotrophs are those organisms that must attain at least some nutrition from feeding or absorption of organic materials to acquire a reduced source of carbon. Even primary producers need more than sunlight to survive, and this is part of a great misconception that autotrophs can exist with only sunlight. Consider the houseplant that dies without nutrients from soil or fertilizer; it obviously needs additional nutrients besides light and water. Consider, as well,
that fertilizers and soils are commonly described by their nitrogen and phosphorus content; these are also among the most important nutrients required by heterotrophic organisms. The main difference between autotrophs and heterotrophs is not that one ‘eats” and the other “just needs sun,’ but that one can provide various amounts of required carbon by using light energy. All animals are heterotrophs, including the corals.

The nutrients available in water to coral reefs can be dissolved in the water, in the form of particulate material, or as living biomass. The word ‘nutrient’ is often misunderstood. The terms ‘high nutrient’ and ‘low nutrient” can be taken in many contexts. In general, nutrients are those organic and inorganic compounds necessary to sustain life. While this comprises a very large group of potential compounds, nutrients are often simplified in terms of those elements that are major ‘building blocks” for lipids, amino acids, and carbohydrates. Furthermore, they are frequently those elements that tend to limit further growth of an organism by their availability
and ability to be procured. In general, carbon, nitrogen and phosphorus are often used to describe the ‘nutrient’ condition of coral reefs and reef organisms (and others, as well). Plants and animals with photosynthetic symbionts, such as corals, tend to be nitrogen and/or phosphorous limited under normal conditions, since photosynthesis usually provides non-limiting carbon source material. Coral reef waters are typically ‘nutrient poor” as they usually contain very low levels of nitrogen and phosphorus (they are both precious commodities and any excess is usually taken up quickly). In nearshore areas where there is significant organic
loading from land runoff, waters tend to be rather “nutrient rich,” or higher in nitrogen and phosphorus. Both types of environments sustain their own flora and fauna with varying amounts of habitat overlap in terms of the organisms that can exploit the continuum of nutrient conditions.

The coral reef is a place of both high primary productivity and consumption of nutrients, with a great deal of nutrients being recycling within the community. For many years, coral reefs were thought to be “nutrient poor deserts.’ In fact, this is not the case. It would be a very poor assumption to imagine any species-rich community that was not highly dependent on nutrients. While measurement of the water column shows it to be relatively devoid of organic and inorganic dissolved nitrogen, carbon and phosphorous, and therefore ‘nutrient poor,” it is largely because of the efficiency of the reef community that such water conditions are attained. Waters around coral reefs are rich in nutrients in the form of various types of plankton; these are largely removed by coral reef organisms. It should be noted that most of the plankton on coral reefs is produced by and lives within the reef or nearby communities, and is not borne into it in great quantities by the open ocean. There are coral reef areas where nutrients are brought upward from the deep ocean, called upwelling, but they are not ubiquitous to coral reefs. There are also seasonal plankton blooms when oceanic plankton levels may be transiently high, but the open ocean is also relatively devoid of nutrients.”

For the full article by Eric Borneman, check out ReefCulture Magazine Edition #4