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Propagating Brain Corals

By Phil Hunt

In his April 2012 article “Great Minds: Keeping Brain Corals in the Reef Aquarium,” Phil Hunt reviews various types of brain corals and the care requirements they have in an aquarium setting. If you are already keeping them successfully, then you might be interested in propagating your brains.

Propagating faviid brain corals is, in theory, relatively simple: Each coral consists of many polyps, and cutting pieces from mother colonies should enable small colonies to be grown on. This needs sharp tools, but if done with care can work well. Once cut, faviid frags, and the mother colony, should be placed in strong water currents and good lighting with excellent water quality. This is to minimize the chances of infections or tissue recession starting from the areas of mechanical damage caused by the cutting process.

Another method that can be used is to carefully break away pieces from the very edge of the colony; when faviid corals are growing well, the skeleton in these areas is often very thin and it is easy to snap pieces off. These fragments can then be attached to pieces of rock and grown on, under good conditions they will fuse onto the substrate quickly. Alternatively, the mother colony can be allowed to extend onto an adjacent rock, then carefully broken away to leave a new small colony behind.

Propagating LPS brain corals can be much easier or much more difficult, depending on the coral in question. Lobophyllia with phaceloid skeletons are very easy to propagate: Individual columns can be broken out of the colony, with no harm done to either the frag or the rest of the coral, due to the lack of damage to soft tissues. For Trachyphyllia, Symphyllia, and those Lobophyllia with more solid skeletons, things are much more difficult. While some hobbyists have successfully propagated such corals by simply cutting up the colonies, cutting through skeleton and soft tissue alike, just like propagating faviid corals, this is a risky procedure that can lead to the loss of the whole colony. Occasionally, corals that have recovered from tissue recession will have areas of tissue isolated by areas of bare skeleton, and these can be divided into new colonies.

Photograph by Phil Hunt.

Posted March 9th, 2012.

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Bag Water: To Dump or Not to Dump?

Jay F. Hemdal

In the March and April 2012 issues of TFH I discussed basic and advanced acclimation techniques. One question that I did not address, but one that commonly comes up in discussions, is whether or not to dump the bag water into the fish tank. Since I was a child, I was always taught never allow any of a fish’s transport water to enter the aquarium during acclimation. The idea that this shipping water is polluted with both organic wastes and fish parasites is common knowledge to everyone, isn’t it? Knowing this to be true, I parroted that advice to thousands of people during my subsequent career in the pet trade and public aquariums. I never thought much about it, it became dogma for me.

What is the truth though? Certainly, animals produce waste, and while they are contained in a shipping bag, these wastes do build up. However, the amount the fish produces is relative to the shipping time, and if they had been in the operating aquarium for that same time, they would have produced the same amount of waste, yet the biological filter would have dealt with it in short order. If the addition this shipping water, with even an extra day’s build-up of wastes would harm the aquarium, then that system has much bigger problems with its biological filtration system that needs to be corrected.

What about the potential for disease introduction? Since the fish is being moved into the tank, it will be carrying any parasites with it anyway, so this is not as big of an issue as one might think. There is one theory though, that promotes the idea that during shipping, many parasites may become dislodged from their host fish, and that by adding shipping water to the tank you are in effect, adding extra parasites. The issue with this is that it has not been microscopically substantiated, nor is there any proof that such dislodged parasites can return and reinfect fish. Finally, if the fish had an infection, it is impossible that all parasites were dislodged into the shipping water, so the fish will still need to be medicated.

There are only two valid concerns regarding not adding shipping water to the aquarium: First, if the fish had been shipped with chemicals added to the water (including copper, methylene blue, or antibiotics) and secondly, the possibility that the water contains higher than normal levels of heterotrophic bacteria. Neither of these are major issues, especially since the first step of the acclimation process outlined here is to remove most of the original shipping water before the process begins.

Go ahead and let the small original volume of shipping water to return to the aquarium. You can then recover all of the tank water you added during additions, plus it is easier to just slide the fish out of the plastic bag. Most of us have had this happen: you struggle to net a fish out of the shipping bag, and you fumble for it as the fish flips out and hits the floor. Fish can be injured by net frames or caught in the net material itself. Some aquarists advocate transferring the fish by hand, but don’t try that with a rabbitfish or some other venomous species! Human hands are not adept at holding struggling fish, so in the end, it may be best to just tip the bag over and slide them out, water and all!

Photograph by AISPIX/Shutterstock


Posted March 2nd, 2012.

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The Yungas

International explorer Heiko Bleher traveled to the Yungas in Bolivia in search of freshwater fish.

By Heiko Bleher

photographs by the author

It was a lovely day in Sarlat, which to me is the most beautiful city of France, in the Dordogne. Sitting in this beautiful old mansion just outside of the city limits, surrounded by greens, plants, trees, and bonsais I was having lunch with Jacques Géry and his wife Georgie. She had served pate du foi gras entier, the whole duck liver, and a delicious red wine, while Jacques was telling me about Nathan Everett Pearson, the student of the famous German/American Ichthyologist  Karl H. Eigenmann (1863–1927), one of the most talented and well respected men in the ichthyological world—the very same which applies to Jacques Géry. Jacques asked me why I had not been to the Yungas on the eastern slope of the Andes in Bolivia. There is very interesting research to be done there. Pearson alone, on the Mulford Expedition of 1921–1922, collected 6775 specimens, of which Characiformes (his lifetime speciality) represented about 50 percent of the collection and 77 of the total of 155 species, there. He found 25 new species and 2 new genera, most of them never seen alive until today.

This tiny characoid was (to me) something special. Less than an inch long, with the brightest golden color and a jet black stripe below the golden stripe all the way into the tail fin, this is a miniature tiny jewel.

Naturally that made me very curious, especially because I collected in Bolivia several times, but never in that region he mentioned. The only other person who did report of some field work in that region was Perugia, who published in Genova, Italy, in 1897 about the collection of 200 specimens Professor Luigi Balzani (Gymnogeophagus balzanii) found in Bolivia. They represented 37 species, out of which 5 came from the Marmoré and 32 from the Beni, in the Yungas. Haseman also collected in Bolivia, but only in the Marmoré/Guaporé region, not in the Yungas or the eastern slopes.

Actually I was very interested in seeing some of those new genera and species in vivo, especially after I researched and found out that no one has ever photographed and much less collected any of those species alive.

The only real predators were members of the wolffish family in a small pond.

Next thing I knew, I was on a plane from Milan to São Paulo and on to La Paz, the highest capital city of the world, which brings back childhood memories. My mother and I took a two-year expedition to South America when I was a child.

The Mulford Expedition

The Mulford Expedition of 1921–1922 was organized by Henry Hurd Rusby to explore the Amazon Valley from the headwaters of the Quime River in Bolivia to the mouth of the Amazon in Brazil. Dr. Rusby, then 70 years old, was a well-known explorer, a professor at Colombia University, and a member of the New York Botanical Garden staff. Funding was obtained from the H. K. Mulford Company. To assist him in collecting and handling plant specimens, Rusby hired Dr. Orland E. White, of Broclyn Botanical Garden.

The expedition started by crossing the high Andes on a mountain trail, passing through the Bolivian Yungas, down the Bopi River by balsa raft, and to the jungle town of Rurrenabaque by way of the Beni River. They searched the Beni savannas for a lake that was rumored to have an outlet to the Beni River. There was no such outlet, so they backtracked to Rurrenabaque. Along the way, five of the eight expedition members departed for reasons that vary from disillusionment to illness. That was in the first year. The remaining members traveled to Manaus in central Brazil, up the Rio Negro, to the Uaupes River, and finally to the Tiquie River where they were blocked by waterfalls and rapids and had to turn around. After a second full year of wandering, the expedition came apart when the final member was left to recover from poisoning in Manaus.


Rurrenabaque was the site of the expedition’s longest stop and the collection point for many specimens. Today it functions as a staging ground for eco-travelers in search of wildlife and adventure. It is a spectacular sight to enter Rurrenabaque by boat from upriver. The narrow gorge is now the grand entrance to Madidi National Park. Rurrenabaque is larger today, but the housing has probably not changed dramatically since the Mulford Expedition.

The expedition started in Rurrenabaque, an area that includes mountains in addition to two other ecosystems.

Rurrenabaque is at the intersection of three major ecosystems—the mountains, the rainforests, and the pampas. The result of this blending is a remarkably high diversity of wildlife, as revealed in the variety of animals collected during their long stay there.


The cries of red howler monkeys were heard every morning.

Every morning, red howler monkeys  made deep, guttural howls and, at sundown, hoatzins (a bizarre bird whose young have clawed wings), squawked in loud bunches along the waterside. The raucous chatter of macaws and parrots periodically penetrated the constant drill of cicadas. A jewel-like dung beetle, in particular, captured my attention. Its beautiful exterior seemed inconsistent with the job it performs in the rainforest animals. We also saw capybaras (a large rodent), a bright green parrot snake, toucans, and delicate butterflies.

The Bolivian government to establish Madidi National Park in 1995. The park is home to 85 percent of the bird species in Bolivia (11 percent of all the bird species in the world), 75 percent of Bolivian mammal species, and 40 percent of Bolivian reptile species. Endangered jaguars, giant otters, spectacled bears, and black caiman all roam within its forests. But, Madidi is not only important because of the rich biodiversity it protects within its borders, but because it is now part of a series of protected areas that stretch across international lines and an eclectic variety of habitats. Madidi, like other protected areas in the Amazon, will survive only if the people who live in and around the park have an incentive to keep it protected.

At the end of the road behind Alto Madidi I was lucky and found this tiny blue shiny tetra.

A proposed dam across the Beni at the entrance of Madidi National Park would flood Chalalan Lodge and surrounding rainforests. The proposal seems to be on hold for now, but there are road projects in the works and two companies hold concessions to search for and extract hydrocarbons within the park’s boundaries.

Posted February 17th, 2012.

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Overconfidence in the Tropical Fish Hobbyist


Skin flukes (Gyrodactylus spp.). Photograph by Craig Adams.

By Craig Adams

“I am God’s gift to koi,” my client began, “or so I thought, until this year.” We were standing at the edge of this gentleman’s pond in late June, who was having unexplained losses and was frustrated in his effort to keep his population of koi healthy. He ultimately lost about half of his large collection before the situation was brought under control. My client has had a 20,000-gallon pond for 20 years with a beautiful collection of koi, many of which were spawned in that very pond. Being a very advanced hobbyist, he even has an 8,000-gallon tropical tank in his yard in western Washingtonthat includes an amazing assortment of large tankbusters, such as Arapaima gigas, redtail catfish (Phractocephalus hemioliopterus), and Colossoma macropomum. He understands water quality, nutrition, and many of the intricacies of husbandry that allow him to be an ultra-successful hobbyist. The koi spawned and raised in his pond were like his children, so thinning their population to an appropriate level was difficult for him to do. Eventually, it caught up with him.

White Noise

Overconfidence can sometimes be damaging because it clouds our judgment and prevents us from seeing what is in front of us. This happened to me recently at home as well. My wife and I were trying to transition our baby girl from sleeping in a cradle in our bedroom to sleeping in the crib in her room. We started the transition by having her nap in the new crib during the day. We ran into trouble, however, because she seemed to be more aware of the everyday sounds around her and had trouble sleeping.

My wife thought that adding some white noise to her surroundings might help to drown out the other noises and let her sleep. Some people use the vacuum cleaner for white noise. There is even a white-noise machine on the market that sounds a bit like the static we used to get from the television in the pre-cable days when we could not get reception. That seemed like a colossal waste of resources to me. It did not take me long to come up with the perfect white-noise generator. I grabbed an empty 20-gallon tank from the workshop next to my fishroom and set it up in the baby’s room. Naturally, this gave me a great excuse to buy some new fish to stock it.

We do not have a large selection of local fish stores in our area, at least for freshwater fish. Since this was an emergency (I certainly could not generate white noise with an aquarium that was devoid of fish), I headed to the local outlet of a nationwide distributor. I chose two of my all-time favorites: angelfish and Corydoras catfish. My wife selected a small school of each species, a plastic sea turtle, and an artificial Amazon sword plant. We were now prepared to convert our baby’s nursery into a white-noise paradise. She would no longer be jolted awake by cars honking, dogs barking, or me tiptoeing down the carpeted hallway while holding my breath.

Once we got them home, the cories quickly began exploring their surroundings and rooting through the sand substrate looking for food. The angelfish established their pecking order and chose spots along the plant and plastic turtle while keeping a keen eye out for the bits of food that magically appeared on the water’s surface a couple of times a day. This was, for all practical purposes, an Amazonian biotope setup from the plastic sea-turtle region of South America. Ahh, fishkeeping nirvana.


Unfortunately, all was not as it seemed—I lost an angelfish on the following day. This is not unusual with a new batch of fish. Just the act of netting fish and transporting them to a new tank can cause stress, elevated cortisol levels, and subsequent reduced immunity. Transport losses are expected to a certain degree, but never welcome. Did I quarantine these fish? No. This was a new setup, but the filter was already mature since I pulled the foam insert from another tank I already had running. I was therefore treating the entire system as a quarantine tank. I would not have thought of putting these fish directly into any of my other tanks that already had fish in them.

Over the course of the next few days, I slowly lost fish, both cories and angelfish. My wife chided me a bit since the big fish doctor was losing fish in his own daughter’s room. I tested the water on a daily basis, as should be done on all new tanks. The filter was functional, and I never recorded ammonia or nitrite spikes. I chalked the losses up to ongoing stress following the move from the store. One afternoon after changing a diaper, I was watching the fish with my daughter. By finally paying close attention, I could see that one of the angelfish was hanging back a little while the others were actively feeding. I decided that enough was enough. I got some of my equipment and performed a skinscraping on that fish—what I found shocked me.


I was dealing with one of the worst Gyrodactylus infestations I had seen for a long time. These are sometimes called skin flukes. There is a similar fluke, Dactylogyrus, which is also known as a gill fluke. They have different life cycles and can be found on the skin or the gills. Gyrodactylus flukes are viviparous (livebearing) while Dactylogyrus flukes are oviparous and have eggs that settle on the substrate to hatch prior to attaching to a host. Gyrodactylids attach to a fish with large anchors present in the opisthaptor (attachment organ). They are quite prolific, and in warm conditions, a population of flukes can double in 24 hours.

Once attached, they scrape mucus and epithelial cells from the host. This leads to irritation, excessive mucus production, secondary infections, and even respiratory distress if they are on the gills. They can quickly kill fish. One easy way to tell if the fluke is a gyrodactylid or a dactylogyrid is to look for the presence of an embryo in the fluke. The hooks on the embryo are often visible. These are microscopic parasites, so you will not see them with the naked eye. Excessive mucus on a fish is a clue, but it is not enough to make a diagnosis of a fluke infestation. Both of these are monogeneans—they do not require an intermediate host as part of their lifecycle. Digeneans, in contrast, are flukes that do require an intermediate host, such as a snail or a worm.


Well, once I had a diagnosis, I felt a little foolish. I had been operating under the false assumption that the problem was just stress related. Stress certainly could have played a role, but ignoring the problem would not make it go away. I added 2.5 ppt pickling salt (sodium chloride without anticaking agents) and 15 ppm formalin every other day with 50-percent water changes on the off days for three treatments. The salt was added to help reduce the osmotic stress that the fish were experiencing. Formalin is an aqueous solution of formaldehyde gas. As you can imagine, it is a dangerous substance to deal with if not handled properly. I happened to have some on hand since it is an approved medication for some food-fish diseases, so I decided to use it.

Most of you will not have it at home, and you would not know where to get it if you needed it. There is, however, a much safer alternative called praziquantel, which is a medication used to treat tapeworms and other parasites. There is a good chance that if you have a dog or a cat, your veterinarian has used it on your pet. Many of my fish patients live in ponds, and treatment with praziquantel can be very costly when such a large volume is needed, but treating an aquarium (even a large one) can be done for a reasonable price, usually less than the cost of replacing all the livestock.


Like a contractor with a home that has an unfinished basement or a painter with psychedelic wallpaper from 1970, the fish vet can have losses in his own tank. Once we step back, analyze the problem, and determine what is going on, the proper treatment becomes less of a mystery. Wait-and-see is not usually the best course of action. Most veterinarians could diagnose a fluke infestation in a fish whether they know it or not, but few veterinarians will travel to your house to make the diagnosis (although a growing number of us will). If you have a very sick or freshly dead fish and suspect flukes, you can put it into a bag for the veterinarian to look at in the office. Once you have a diagnosis, a treatment plan can be arranged to try and save the rest of the fish in your system.

Just adding one of these new fish to any of my existing aquariums could have led to the death of many of the fish already in my collection. That would not look good for a fish doctor. Always remember to quarantine. Your fish will thank you for quarantining, and they may even start to refer to you as “God’s gift to fish”!

Posted January 23rd, 2012.

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Temperature Determines Gender


European sea bass were used for studies looking at the effect of temperature on gender determination in fish.

The environmental temperature has effects on sex determination. There are species, such as the Atlantic silverside fish, whose sex determination depends mainly on temperature. And there are other species whose sex determination is written within its DNA but still temperature can override this genetic ‘instruction’.

Previous studies with the European sea bass, a fish whose sex determination depends on a combination of genetic and environmental factors, had shown that starting with a normal sex ratio population -equal proportions of male and females, it was possible to obtain an all-male group just through an increase in water temperature during a critical period of early development.


Photograph by Imagine Images/Alastair Pidgen/Shutterstock

Posted January 3rd, 2012.

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