Ichthic

Sebastolobus altivelis: Longspine Thornyhead

2008-09-24T01:16:00.002+01:00

Recorded as being discovered in 1896, the Longspine Thornyhead, known in the fishery trade as the idiotfish because of its bug-eyed appearance, is now considered to be in danger. In the last ten years alone the population of S. altivelis has dropped an amazing 50 to 60 percent. The decline in population is largely due to the unchecked harvesting of this species by fisheries.

The Fish’s Appeal

S. altivelis is considered to be a delicacy in Japan, and this is where the majority of the harvested fish have ended up. The Longspine Thornyhead, according to fishbase.org, is not currently marketed in the fish keeping hobby. Due to its current decline in population, I feel that it may find difficulty becoming part of it, at least in the near future. In addition to population problems, the fish lives in a unique environment.

Habitat

The fish inhabits the depths of the Eastern Pacific Ocean where growth is slow, pressure is high, and oxygen levels are extremely low. In addition to these already difficult conditions where few species live, food is extremely scarce. It has been speculated that the Longspine Thornyhead only eats every few months, if not longer. Without a doubt, this fish is an amazing testament to nature’s adaptive abilities.

Characteristics

Like most rockfish, the Longspine Thornyhead is a mostly sedentary creature with a slow metabolism. This aids the survival of this fish in its complex environment.

The fish breed in spring, laying egg masses that remain near the water’s surface until hatching. As they grow, the fish progressively move toward the depths of the ocean where their adult counterparts live. S. altivelis usually reach no more than a foot long and are estimated to live as long as 45 to 70 years in the wild; although, few in depth studies have been done on the lifespan of this fish.

The easiest way to describe the appearance of this fish is to recall an early episode of The Simpsons. The fish pictured was an orange, spiky, googly-eyed creature with a similar dopy appearance. Of course, S. altivelis has two eyes instead of three.

Conclusion

This comical looking fish, with beautiful coloration in my opinion, has led an amazing and difficult existence. However, it faces a daunting predator: the human taste bud. Sebastolobus altivelis has only been recorded in existence for just over 100 years. And in the last 10 years, we have managed to threaten its survival. With its survival in question, fish enthusiasts must wonder if keeping this fish in captivity is possible. Is it possible to recreate its environment and breed this fish? Is it worth it? Personally, I feel that it would be a disgrace to lose this marvel of nature and is well worth the effort to preserve.

Resources: First photo credited to NOAA. Second photo retrieved from Wikipedia. Other information retrieved from David Suzuki Foundation; fishbase.org; Fisheries and Oceans Canada; Benthic Canada.

Cycling Your Aquarium: Almost as Easy as Riding a Bike

2008-09-22T23:37:00.014+01:00

Every new aquarist is faced with the cycling of an aquarium. However, this important concept is readily misunderstood or overlooked by many new to the hobby.

The nitrogen cycle is referred to in many ways by fish hobbyists: cycling, nitrogen cycle, biological cycle, etc. When you hear these terms, it can be a whole new world, especially if you’re not that keen on science. In actuality, it’s not as difficult a concept to grasp as it first seems. In this article, I will provide the basics on cycling.

Cycling Basics

There is a type of bacteria known as nitrifying bacteria. There is more than one type, actually, but for our purposes we’ll consider them to be one group. This bacteria is present almost everywhere.

The cycling process begins after you set up your aquarium, fill it with water, and provide a source of ammonia for the bacteria to “feed” on. Without the ammonia source, the tank will not cycle. In the diagram given, to the top left, the source of the ammonia is the fish’s waste and excess food given to the fish. The bacteria change the harmful, even deadly, ammonia produced by the fish and food into nitrite. Once transformed to nitrite, another still dangerous chemical, the bacteria change the nitrite into nitrate (note the spelling difference).

Nitrate is much less harmful than both ammonia and nitrite. Nitrate is the final product, if you will, of the cycling chain. Nitrate is harmful, however, in certain quantities. The amount usually considered to be harmful is above 40ppm (ppm: Parts Per Million) on your test kit. This chemical is easily controlled with regular, sufficient water changes.

Water changes are also helpful during the cycling process, depending on how you choose to cycle. Once the process has finished, your test kits should register no ammonia and no nitrite in your aquarium. Nitrate should be within safe parameters, less than 40ppm, and your bacteria colony should now be established and ready to maintain a balance in your aquarium. There are a few ways you can achieve a fully cycled aquarium, which will be listed below.

Cycling with Fish

One of the more common ways to cycle an aquarium in earlier years, and even today, is to add one or two fish. The fish, as shown in the diagram, will provide a source of ammonia from their waste and from excess food in the aquarium and the cycling process will begin. If choosing this method of cycling, you must be careful in how you go about it.

For one, you cannot add too many fish. A couple of fish is usually sufficient, depending on the size of the aquarium. If you add too many fish or overfeed during cycling, you will create much more ammonia than necessary. Any level of ammonia is harmful and is not present in a healthy, cycled aquarium. While cycling, you have to combat the production of ammonia to insure that your fish will survive the process. Small, regular water changes are suggested to protect the fish during cycling. (Remember, water changes help to remove the chemicals, but some level of ammonia must be present to cycle the aquarium.) You will have to continue to monitor the water parameters (ammonia, nitrate, nitrite) closely as well as perform the water changes until the end of cycling to keep your fish from being harmed.

Most fish and pet stores will suggest you cycle with a goldfish. I could not disagree more. Goldfish grow far too large and create emmense amounts of waste. In the end, it's best to choose a fish you will be keeping and can care for.

For the safety and concern of the fish, I do not recommend cycling with fish.

Fishless Cycling

There are a couple of ways to cycle your aquarium without putting lives at danger. Again, you have to provide a source of ammonia for the bacteria to become established. This source can be pure ammonia you can purchase from a store, pharmacist (chemist), or the like. In some areas of the world, pure ammonia is not as easily obtained, and you will have to look to other sources.

Decaying Matter

As gruesome as it sounds, it is effective. If you cannot find pure ammonia and are opposed to using live fish, you can add a dead prawn or shrimp that would normally be used for human consumption. The decaying prawn will provide a source of ammonia for the bacteria, and the cycling process will continue. With this method, since there are no living creatures in the tank, you do not have to do small water changes.

Seeding the Tank

This method proves to be an almost instant cycle. Not only does it add a source of ammonia, but also adds established bacteria to your tank. Here is how it’s done.

Once your tank is set up and filled with water, you can add filter media from an already established aquarium. The media is best obtained from a cycled tank you already have running or from another hobbyist. You can ask a fish or pet store for filter media from one of their tanks, but you are also opening up your aquarium to any disease or parasites that might be carried in the media.

As with any of these methods, it is necessary to have test kits to measure the ammonia, nitrite, and nitrate levels at least. Once your tank is cycled (ammonia=0; nitrite=0; nitrate=less than 40ppm), you're ready to add fish. It is recommended that when adding fish to your newly established aquarium you do it slowly. Don’t misunderstand the concept; fish will still produce ammonia, but if added in the right amount, the bacteria that has become established in your tank should be able to convert the dangerous chemicals without causing harm to your fish.

Resources: thekrib.com; freshaquarium.about.com; personal experience and knowledge. Diagram by Leah Curtis.

Fish Anatomy - Important Things to Know

2008-09-22T04:52:00.016+01:00

Where better to start this blog than the basics? The following article consists of various information that every fishkeeper should know; from the basics to detailed anatomy.

This article intends to cover the general external and internal anatomy of fish. Since the information and pictures provided were originally collected from a fishery site, I have tried to reorganize and adjust the information to target the fish keeping hobby. Credit for the source of the pictures is given to myfwc.com.

Why is it Necessary to Understand Fish Anatomy?

As fish hobbyists who aim to keep healthy aquariums and fish, a basic understanding of their anatomy and physiology is necessary. We often find ourselves stumped by or battling with a disorder or disease in our home aquariums. By understanding the anatomy of our fish, it is possible to grasp a better understanding of what has become compromised in the fish itself.

The following is a list of the primary organs, their functions, and possible malfunctions. It has been alphabetized for convenience.

Brain

The brain, as in any animal, serves as the control center of the fish’s body. It receives and interprets signals from other parts of the body. It “tells” the rest of the body what to do and serves in the functioning of the nervous system; pain reception, homeostasis (the healthy balance the fish must maintain), and decision making.

Gills

The gills aid in respiratory functions. Many problems may occur with the gills; rust (a red dusty appearance, usually occurs on bettas), Ich attached inside the gills, etc. One can also observe the gill beats. Much like observing the heart beat of humans, it’s possible to watch for the amount the gills beat within one minute. An increased gill beat means that the fish is struggling to breathe or is under stress.

Gonads – The Reproductive Organs

Understanding the reproductive system of fish is necessary for successful breeding and sexing of fish. Cases where this information would be necessary are situations like sexing young livebearer fry for separation, determining whether or not a female livebearer is pregnant and soon to give birth (by observing the appearance of the vent-gravid spot). Common male livebearers are easily distinguished from females in that their fins located near the vent, when mature, develop into a gonopodium (aids in the transfer of sperm to the female during reproduction).

In the rearing of livebearers in overstocked or poorly kept aquaria, the reproductive organs may be ambiguous, difficult to sex-hermaphroditic, in young fry. This problem is often encountered by newer hobbyist wishing to breed their fish or in small tanks becoming overpopulated. Some livebearers, like Swordtails, are capable of changing their sex from female to male in certain instances.

Heart

The heart is part of the circulatory system; this system transports nutrients and oxygen to other parts of the body and transports waste products for removal. Some of these waste products are carried to the kidneys and removed from there.

Kidneys

As previously stated, the kidneys aid in the removal of waste from the blood. The kidneys also aid in regulating the liquid and salt content of the fish’s body. This regulation is how different fish are able to live in fresh, brackish, or saltwater aquariums. Some fish, like mollies, are able to adapt to different salt contents in water, e.g. brackish fish living in freshwater. However, as a rule, fish do better in the type of water they came from; saltwater fish in saltwater, freshwater fish in freshwater, and so on. The kidneys are one of the organs affected by the disease Dropsy, which causes the organs to expand within the fish’s body increasing pressure and causing bloating.

Lateral Line

The lateral line helps fish to maintain equilibrium or balance. It also detects vibrations in the water, sort of like hearing. In some cases, a fish’s lateral line can become damaged or diseased. Head and lateral line erosion (Hole in head disease, lateral line disease, etc) are when these areas begin to deteriorate slowly. This inhibits the swimming and balancing abilities of the fish.

Liver

The liver, like the kidney, allows for the removal of waste products. It filters, in a sense, materials entering the blood and allows for nutrients to enter the blood. One of the waste products that it aids in removing is nitrogen, familiar to the aquarium chemistry.

Muscles

Fish muscles, like the muscle tissue in other animals, help the fish to move. They also store essential materials and hold the fish together, in essence. The muscles are the meat of the fish and are generally what becomes infected and deteriorates when problems arise. One can imagine that when this tissue is attacked by a disorder, the normal functioning of the fish is at risk.

Spine

The spine of the fish runs horizontally from the base of the fish’s head to the tail fin. The spine provides support and a center point for the rest of the body. The spinal cord, within the spine, is part of the nervous system. When the spine is damaged, either from birth defect or disease, such as Tuberculosis, the nervous system becomes compromised. In addition, the fish becomes deformed and such an injury may lead to paralyzation or death.

Stomach and Intestines

The intestines and stomach are part of the digestive system. Food matter is digested and passes through them until exiting the body of the fish. Fish may contract intestinal parasites that inhibit the fish’s ability to digest and use the nutrients the fish needs. Another problem that may occur is a blockage or constipation. The undigested food and waste begins to build up in the intestines and press against other vital organs; Example: the swim bladder. This can lead to a Swim Bladder Disorder (SBD), which could lead to death if the fish is unable to eat and swim properly.

Swim Bladder

The swim bladder is a vital organ in the fish anatomy. Basically, the swim bladder is an air filled organ that allows the fish to swim normally and maintain balance. The pressure within the organ and from the outside water changes depending on the depth of the water. This allows the fish to sink or float as necessary. If the organ is compromised, whether it be deformity, infection, trauma, or constipation, the fish loses its balance and begins to have difficulty swimming. Swim bladder disorders, depending on severity, can lead to death. This problem must be corrected.

Vent

The final part of the fish’s anatomy relevant to the fish hobby, is the vent. Briefly touched on earlier, the vent generally refers to the anus of the fish where waste is removed from the body. The term vent may also be applied to the end of the birthing canal in female fish.

Hopefully this detailed glossary of terms helps you in understanding the fish you keep and with any problems that may arise.

Resources: myfwc.com; knowledge gained from fishkeeping and prior reading, scientific knowledge.