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Keeping Altolamprologus Species

Altolamprologus compressiceps. Photograph by MP. & C. Piednoir.

By Chad Christensen

Altolamprologus calvus and A. compressiceps hail from Africa’s Lake Tanganyika. The genus Altolamprologus is limited to these two species. They belong to the family Cichlidae, which has an astounding number of described species worldwide, with many still undescribed and countless varieties and subspecies.

A Complicated History

A. compressiceps was originally described as Lamprologus compressiceps in 1898 by Boulenger. Originally thought to be only one species, it was observed by Pierre Brichard on a 1975 collecting trip that there were some variations in collected “compressiceps.” In 1977, after placing two fish of equal length in a collecting bucket, Brichard realized that he was dealing with two distinct body shapes. He provided Poll with a sufficient supply of speciments and further analysis revealed several more differences which supported the creation of a second closely related species, calvus, in 1978 by Poll. The Latin word “calvus,” meaning bald, was a suitable species name, because, when compared to compressiceps, the calvus lacked scales on the upper portions of the head.

The genus Lamprologus was revised by J. Colombe and R. Allgayer, though Poll later rejected two of three genera and created and redefined the Lamprologus genus. At that time he also erected the genus Altolamprologus for calvus and compressiceps. Most other Lamprologus species ended up lumped into the grab-bag genus Neolamprologus. Dr. Paul Loiselle notes that both studies focus on superficial characteristics and he, and many others, see little value in adopting the name conventions proposed in these destabilizing nomenclature studies until modern methods can verify their validity.

Genus break up and reclassification is a constant game and has been the cause of more than one stern discussion. Remember the ongoing Cichlasoma reclassifications? All the hobbyist can do is be aware of the proposed changes, accepting them gracefully, and realize that a particular fish by any other name is still a fish…the same fish.

Altolamprologus Basics

A. calvus and A. compressiceps share the same basic body shape. They have high bodies and are quite laterally compressed, hence the original species designation of compressiceps. This lateral compression greatly enhances the ability to pick invertebrates and other edibles from the tiniest crevice. Also documented in this genus is the ability to rotate the eyeballs to a nearly 90° angle with the normal plane, allowing these fish to slowly scrutinize the crevices where they might encounter their next meal.

The compressed body shape not only enhances the ability to forage, but permits defensive concealment. Fitting into small crevices is advantageous in avoiding predation. When these fish lodge themselves in these small places, they tense their bodies in such a manner that spiny fins and scales lock them into place and it is nearly impossible for a predator to pull them backwards out of their cover. When confronted by an aggressor, a similar defense is often invoked in open water. The fish turns sideways and curls away from the bite of the aggressor, thus providing a less vital, scale-flared flank as a target. This is apparent in the aquarium when an over enthusiastic male bullies a smaller female.

The two species can usually be distinguished from each other with very little scrutiny. A. compressiceps has a noticeably higher neck/back when compared to A. calvus. A. compressiceps also has a more upturned mouth, giving their head a shorter, meaner, more pug-like appearance. Both calvus and compressiceps come in a variety of flavors. The color variety depends on the geographical location from which they were collected.

A. calvus (pictured) features a shorter neck than A. compressiceps. Photograph by MP. & C. Piednoir.

It should be noted that calvus and compressiceps do inhabit the same areas and, to my knowledge, no naturally occurring hybridization has been reported or theorized, though this will occur in the extremely unnatural environment of the aquarium. Some color varieties and geographical varieties of A. calvus include the blacks from Cape Chipimbi, Zambia, and from Zaire (now Congo). Yellows come from various Zambian locations, including Nangu Island, Nkamba Bay, and Chilange Rocks, and whites come from Cape Chaitika, Zambia. Some varieties of A. compressiceps include oranges/golds from Cape Chaitika, Zambia and Kigoma, Tanzania, red-fin varieties from Tanzania, and four gold head varities from Malasa Island, Tanzania, Kalambo, Muzi, Tanzania, and the rarer Mutondwe Island, Zambia, which is the only described compressiceps variety to exhibit blue in the fins.

Altolamprologus species come in a number of different color varieties. Photograph by Mark Smith.

Both species have a maximum size of a little over 6 inches for males and 4 inches for females. One noteworthy exception is the dwarf Altolamprologus—one from Sumba Bay, Zambia, and another from Mbita Island, Zambia. These fish may reach only about 3 inches in adult males with the females smaller still.

The species of Altolamprologus, like many other Tanganyikan species, are slow to sexually mature, and they are also an extremely slow-growing fish. Fry of a captive spawn may only reach 5/8 inch in three month’s time 2 inches in a year, and it may take as long as two to three years for the fish to sexually mature, depending on conditions. With this said, it should be no surprise that there is a large difference in price between small fry, larger fry, young adults, and breeding adults. A faster growth rate will be noticed with high quality, a varied diet, and plenty of water changes.

Keeping Altolamprologus Species

Aquarium requirements for Altolamprologus spp. are not unlike those of other Tanganyikan fishes. The extremely hard, alkaline waters of Lake Tanganyika should be simulated in the aquarium. Some people will have local tap water that will suffice, while people from other areas may require chemical manipulation with additives to bolster the mineral content and pH values. The pH of an aquarium housing Tanganyikan species should always be above 7.5, but preferred pH values are between 7.8 and 8.6. It should be noted that ammonia is far more lethal the higher the pH, so great care should be given to providing exceptional biological filtration and regular water changes must be performed.

While hardness is a less critical parameter than pH, achieving water with a medium hardness value or harder is a reasonable goal. Being as Lake Tanganyika is actually so hard that it precipitates calcium, fusing the bounders of the rocky shoreline together, the hobbyist would be hard pressed to provide water that is too hard. Also, the extra hardness provides protection from pH drift and crashes. One important thing to remember is these species are extremely sensitive to chlorine and chloramines, so a suitable dechloraminator should be used.

Lake Tanganyikan cichlids come from exceedingly hard water and therefore require at least medium-hard water in the aquarium. Photograph by MP. & C. Piednoir.

Water temperatures between 76° and 80°F are the best, with 78° proving to be safe medium. Temperatures above 84° are often fatal. The higher the temperature, the more important it is that the water be saturated with oxygen. As the temperature approaches the 84° mark, the fish can and will suffocate if the water is not 100 percent saturated with oxygen. Tanganyikans tolerate temperatures that are too low better than they do ones that are too high. Aquariums will lose heat through evaporation, so they tend to remain several degrees cooler than the room temperature if no other means of heat are provided (heaters, submersed pumps, etc.). If the aquarium is situated in a room that will remain higher than about 85° for any amount of time, such as a non-air conditioned room or a garage in the summer, action should be taken. One way to aid evaporation and help prevent the tank from overheating is to provide extra water circulation with airstones or have a fan blowing across the surface of the water. Opening up the aquarium hood will aid evaporation, although it’s risky with species with that are known to jump. A. calvus and A. compressiceps are not known to be jumpers, except in possibly extreme cases of interspecies aggression or, of course, when being chased by a net.

Most all types of flake foods are accepted. A varied diet will help keep the fish healthy and condition them for breeding. Meat should be added to the diet—live or frozen brine shrimp, as well as bloodworms, are greedily accepted. Live or frozen baby brine shrimp and crushed flake foods are suitable for fry.

Substrate choices are the usual fare of gravel or sand. Crushed coral is another option which helps to raise and stabilize the water’s pH. If gravel is used, a natural brown or darker color is preferred to give a more natural environment. Sand also makes a wonderfully natural substrate. No matter what substrate is used, it should not be deeper than about one inch because without water circulation, the substrate will harbor anaerobic bacteria. An effort should be made to mix up the substrate after siphoning detritus off its surface during weekly water changes. While plants are not a natural part of these species’ biotope, both live and imitation plants may be employed at the hobbyists’ discretion.

In small aquariums (20 longs or 29-gallon), these fish are best kept in pairs or trios, although many can be grown to sexual maturity together. Once fish begin to breed, male conspecific aggression escalates to the point that all subdominant males must be removed for their own safety. In a fairly large aquarium (75 to 135 gallons), more than one male can sometimes be kept successfully. With any size aquarium, having a variety of caves of rockwork is the key to success. Males are fairly hard on the fames so, room permitting, more than one female should be kept with the male. A 40-gallon breeder or a 55-gallon tank will house a male and several females, as well as the desirable addition of dither and/or target fish.

The importance of having a variety of caves, rockwork, and shells cannot be stressed enough. These fish are shy and skittish. Having more hiding places available will make them feel secure and you will actually see them out and about more than if you had less hiding places. Knowing a safe haven is close by makes them much bolder.

Having plenty of Caves, rock work, and shells will reduce aggression in the aquarium and make the inhabitants bolder. Photograph by Mark Smith.

Spawning Altolamprologus Species

Providing a variety of caves also gives the females a better chance of avoiding unwanted advancements by the males. Again, this is where having more than one female is a help—it divides the male’s aggression between more fish so no one fish is relentlessly harassed. Shells should be provided for the females to spawn in, though they are not required. Females will also spawn in caves, but shells are often used due to the convenience for the hobbyist.

Using an appropriately sized shell is important: If the shell is too small, the female can’t fit into it but it’s too big the female can fit too far into it. If the female gets too far into the shell, she may become stuck and also, the hobbyist doesn’t know when the shell is occupied since the fish enters far enough into the shell that no part of the fish is visible.

Another problem with having too large of a shell has to do with spawning itself. The male may also try to enter the shell, which may not allow the female the much deserved break from aggression. If the male does not enter, and the shell is large enough to allow the female deep access, the male may be unable to fertilize the eggs, since the males often simply release their milt near the shell entrance and both fish fan it in towards the deposited eggs. Even if the eggs do get properly fertilized, there is still the risk that they will perish. The clutch of eggs needs constant circulation of clean, aerated water, which the female usually supplies by fanning the eggs. If the eggs are deposited too far into the shell, well away from the opening, the female may be unable to provide the required circulation, despite her best efforts.

The best size shell is one that the female’s caudal fin is visible when she is nestled as far in the shell as she chooses to go. This lets the male easily fertilize the eggs while she still is, for the most part, out of reach of his aggression. Unlike in a larger shell, she can block the opening with her body to guard the eggs and fry. The clutch is close enough to the shell opening that the female can fan a respectable amount of fresh water across them, and the hobbyist can rest assured that he or she knows where the fish is located at a glance.

That being said, a properly set up aquarium should provide more cover than only shells. Shells will be used for shelter if nothing else is available, but males and females alike prefer a cave of some type for non-breeding shelter. This also makes it easier for the hobbyist to know when spawning has occurred, since a female will only be in the shell if she is guarding a clutch. At least one cave should be provided for each fish and, in addition to that, one shell per female. Males will spawn with any females that are ready, and if enough suitable spawning sites are provided, there will often be more than one female guarding fry at a time. The last reason that shells can be considered the best spawning site is a selfish one for the hobbyist: Shells are an easy vessel from which to gather fry. After females have been in their shell for eight to twelve days, the fry can be harvested for transport to a small grow out tank.

Raising the Fry

When gathering the fry from the shell, care should be taken not to let the fry be out of the water any more than can be helped. One of the easiest ways to remove the fry is to prepare a container with water from the aquarium from which the fry are being removed. A clear specimen container works well for this and has the added benefit that it can be hung on the aquarium, preferably on the inside. Grasp the shell and hold it at or near the water’s surface over the container. Rotate the shell in the proper direction to flush out the water. More than likely, the female will remain in the shell, but this is a minor inconvenience since the fry will flow past her and out into the container. To decrease a mother’s physical stress, however, one should attempt to capture the shell while the female is away. After each flushing the shell should be immediately dunked into the container, allowing the shell to refill with water. Rotate the shell to let the air out if necessary. Again, the shell should be raised to just above the surface and flushed. This can be repeated until no more fry flow from the shell.

At this age, the fry still have the sticky area on their heads which allows them to stick to the cave or shell walls and one will notice as they are flushed out into the container that many of the fry are also stuck to each other in little masses. This also makes fry removal a bit harder, but it is helpful to shake the shell, with some water in it, between dunks to free the fry from the shell wall. One could wait and let the fry develop another four to six days into free-swimming fry, but then the hobbyist runs the risk that the fry will swim out of the shell or be flushed out during a water change—been there, done that. Once removed from the safety of the shell, the miniscule fry can easily fall prey to other aquarium inhabitants, perhaps even to dad. While the fry-eating propensities of parental Altolamprologus spp. have been greatly exaggerated, it should be realized that every fish is different and some fish may graze on their offspring. As a friend once told me, the fish don’t read the books, so experimentation would be the only way to discover each fish’s parental abilities.

There is no doubt that some spawns will be lost before the parents settle down and become better parents, but this is often true for many other species. Most hobbyists will not be willing to risk losing the fry to overly predacious parents and will want to remove the fry before they are free swimming. While I currently follow this line of thinking, I must say that watching a pair of Altolamprologus with a tank full of offspring can be very interesting.

To this regard, I can give an account of a wild-caught pair of A. calvus that I kept many years ago. Fry were allowed to grow to nearly ¾ inch before the parents were removed and no cannibalism was detected. I observed, however, that the movement of the fry on the substrate would elicit an immediate predatory reaction from the adults until the fry was recognized as a son or daughter rather than a tasty little invertebrate hors d’oeuvre, at which time the fry’s life was spared.

If a pair is kept alone, there is the risk of the pair bond breaking down due to over aggression. Again, this is where it is beneficial to have several females to one male. An alternative is to use some type of target fish. Target fish will also double as dither fish, giving the Altolamprologus an added sense of security and keeping them far more active and visible. Species that prefer the upper portions of the water column are preferred since there will be no direct competition for territory. There are many species that would be suitable, including various danios, rainbowfish, and larger varieties of killifish. For the Tanganyikan purist, Lamprichthys tanganicanus killifish would be a good choice. An equally appropriate choice would be a group of Cyprichromis or Paracyprichromis. No matter what species are selected, ensure that they are large enough or quick enough to avoid becoming a meal.

Get Your Own Altolamprologus Tank

Species of the genus Altolamprologus are a real joy in the aquarium and easy to keep. They make a great species tank, but do equally well in a community situation. The unique body shape and interesting behavior make it well worth the effort to acquire and keep them. The only hard part is deciding which one geographical color variety you like the best. Well, okay maybe just two tanks with different varieties. Do I hear three?

Posted August 24th, 2012.

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5 Fantastic Aquarium Plants

By Rhonda Wilson

For the 60th anniversary issue of TFH, I thought it would be fun to do a list of my top aquatic plants. Of course, I had to decide what sort of top list it would be. In the end, after considering various choices, I decided to include all the options. I chose a mix of plants, some because of their ease of growth, some from their popularity among aquarists now and over time, and some of the ones most likely to be found in the shops. I thought I would do a top-10 list but decided that I had 15 plants I wanted to include, and since it’s all kind of an arbitrary list, that’s what I ended up with. For space considerations, I could only list the top 10 in the magazine, but here are my remaining five favorite aquarium plants.

11. Java Fern

Java fern. Photograph by Mark Smith.

An easy plant to grow for most aquarists and a general all-around favorite, Java fern can tolerate a good range of water conditions and lighting levels. I did have some trouble with them in the water in Phoenix, but they did well with additional CO2. I know most people can grow it with ease in most tap water. Since I recently moved, I’ll be trying it again in my new water. There are several different, very attractive varieties of this fern that can often be found in good pet stores along with the original type of fern. Java fern is particularly well suited to be tied to wood in the aquarium.

12. Cryptocoryne wendtii

Cryptocoryne wendtii. Photograph by Rhonda Wilson.

Cryptocoryne wendtii is a wonderful crypt that comes in a variety of colors and is often available as a potted plant in chain and locally owned aquarium stores. The plants are medium in height and can be used as taller plants in very small tanks and midground ones in moderately sized aquariums. Cryptocoryne can be slow growing but over time easily cover and take over an entire aquarium, with little plants spreading under the substrate. It is also easily propagated from cuttings.

13. Rotala rotundifolia

Rotala rotundifolia. Photograph by Bryce Millar.

Rotala rotundifolia is of the few red plants that will grow under less-than-ideal conditions. The color can range from yellow to pink to peach to red depending on the conditions and lighting it’s grown under. Rotala seems to be happy in a range of conditions and will even tolerate moderate lighting. It does much better with higher light levels and generally gets more red in the leaves under better conditions and lighting. Under optimal conditions, it will send branches across the ground to spread the plant.

14. Guppy Grass (Najas spp.)

Guppy grass. Photograph by Rhonda Wilson.

Guppy grass (Najas spp.) is a long-time aquarium favorite, though it’s not usually found in the stores but is traded regularly at most aquarium clubs. It grows quite rapidly in most conditions and makes for a great plant for hiding fry, which is why it became popular among guppy breeders, hence the name “guppy grass.” The major issue with guppy grass in a mixed planted aquarium is that it grows very rapidly and breaks apart quite easily. Each little node is quite happy to start making a new plant, so it’s very easy to end up with these in places in the aquarium where they’re not really wanted.

15. Bacopa monnieri

Bacopa monnieri. Photograph by Rhonda Wilson.

Bacopa monnieri is a stemmed plant that is very interesting in its structure, with a strong, thick stem and leaf. It looks like a type of succulent. Bacopa not only grows well in the aquarium but is happy to grow right out of the tank where it freely blooms with small white to violet flowers. I’ve gotten to the point where I usually just plant these at the back of the tank and let them go ahead and grow out. They can drape down the sides of the aquarium and be quite attractive if allowed to grow that way.

Pick Your Own

This is just a brief review of some of the aquarium plants that have been the most popular and easiest to grow over the history of the hobby. There are many more plants available, along with undiscovered ones that may become favorites in the future. Be sure to comment and let us know which plants are your favorite for the aquarium!

Posted July 27th, 2012.

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Stocking a Nano Tank

By David Bell

In the June 2012 issue of TFH, I described how I started in the world of nano aquariums. A huge part of my careful planning was identifying what animals I wanted and developing a stocking list.

My must-have fish was a mystery wrasse. I also wished to keep a mix of a few very colorful and smaller fishes such as the secretive fairy or flasher wrasses, demure damsels or percula complex clowns, cardinals, small basslets or grammas, blennies or gobies, and perhaps others to observe their interesting behaviors. I developed the system around those wants. I have basically stuck with my original intention of housing a fish population that averages an adult size of about 3 inches or less. Also, I have always been interested in maintaining a tank exclusively full of hardy and vibrant corallimorpharians, zoanthids and some of the octocorals, as well as a few of the hardier stony corals such as members of the families Faviidae and Mussidae.

Then the challenge came in stocking the aquarium with the right mix of species and number of individuals. I did not plan to have any individuals which would later be moved to a larger tank because they grew too large or acted too aggressively. (However, I do have a seasoned tank already prepared which has come in handy in emergency situations, although it should not be absolutely necessary if the tank is planned correctly.) Ultimately though, I intend to combine this nano reef with one or two other smaller reef systems into a large reef system.

I wound up with this list to begin with.


1 Starry Blenny (Salarias ramosus)

1 Talbot’s Damsel (Chrysiptera talboti)

1 Percula Clownfish (Amphiprion percula)

1 Royal Gramma (Gramma loreto)

1 Tricolor Fairy Wrasse (Cirrhilabrus lubbocki)

1 Mystery Wrasse (Pseudocheilinus ocellatus)


Zoanthids of 14 varieties

Octocorals: Kenya Tree Coral (Capnella imbricata) and Clove Polyps (Clavularia spp.)

Corallimorpharians: Discosoma spp., Rhodactis indosinensis, and Ricordea florida

Duncan Coral (Duncanopsammia axifuga)

Green Plate Coral (Fungia spp.)

Candy Cane Coral (Caulastrea spp.)

Green/Pink Brain Coral (Trachyphyllia spp.)

Green Brain Coral (Acanthastrea spp.)

Red/Dark Red Brain Coral (Acanthastrea spp.)

Pink/Orange Brain Coral (Acanthastrea spp.)

Green/Cream Brain Coral (Favia spp.)

Bright Green Brain Coral (Favites spp.)

Turquoise Brain Coral (Favites spp.)

Red/Blue Micromussa Coral (Micromussa amakusensis)

Multicolored Button Coral (Scolymia spp.)

Red/Orange Button Coral (Lobophyllia spp.)

Other Invertebrates

5 Turbo Snails (Nerita funiculata)

5 Red-legged Hermit Crabs (Clibinarius digueta)

5 Nassarius Snails (Nassarius spp.)

1 Blue Tuxedo Urchin (Mespilia globulus)

Be sure to check out the July 2012 issue of TFH to find out about the progress of these animals, how to overcome challenges presented by nano tanks, and see how it all turned out.

Photograph by David Bell.

Posted May 17th, 2012.

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The Pearl Danio

The pearl danio. Photograph by Tony Terceira.

By Jennifer Wilkinson

Pearl danios (Danio albolineatus) are pretty little fish that are found in the streams and rivers of Southeast Asia: Burma, Thailand, Sumatra, and the Malayan peninsula. Although most of the ones that we see today are bred in captivity in large fish farms or, occasionally, from hobbyists who spawned the fish.
In the right lighting, these are very beautiful fish; they shimmer and glow with a bluish tinge. I noticed that in some pet shops, they just look like a plain gray fish. When mature, the females are quite a bit larger than the males, however the males are the more colorful of the two. They can reach a size of 2½ inches in length.

Keeping Pearl Danios

I purchased five half-grown fish from a pet store and placed them into a 33-gallon community aquarium. First of all, they should have been placed into a quarantine aquarium before being added to my community, however I was very lucky that these fish were very healthy and did not come down with anything. The aquarium contained several pieces of driftwood and some live plants. It also housed two Ancistrus catfish, twelve Corydoras of two different varieties, and two other kinds of danios. The parameters of this aquarium were a temperature of 78°F, pH 7.2, and the water was fairly soft. Water changes of 30 to 50 percent were done twice a week, or anytime that I over fed.
To condition these fish for spawning, they were fed frozen bloodworms, frozen and live adult brine shrimp, and several different varieties of flakes. These pearl danios were always the first in there to grab the food before any of the others had a chance. One has to make sure that enough food is offered so that everyone gets fed.
These fish do not really school, but they do spend most of their time in the top quarter of the aquarium. They would occasionally be found in other areas of the aquarium, but that was usually when they were chasing food. Unlike other danio species that I have kept, the pearl danio is a very hyper fish; it doesn’t ever seem to slow down.


Pearl danios usually breed over fine-leaved plants, however with my fish, it didn’t seem to matter if plants were available or not. In one of my spawns Java moss was available, however for other spawns it was not. It is quite difficult to tell when these fish are actually breeding because they are so hyper all the time. When they are breeding, they dart around quickly, the male beside the female, and they will slow down—not really stop over the plants or whatever else they are breeding over—and release the eggs. The eggs fall to the bottom and will be eaten if they are not hidden or the parents removed right away.
When breeding action was noticed in the 33-gallon community aquarium, the five fish were moved to a prepared 10-gallon breeding aquarium. This aquarium had a 5-gallon black undergravel filter plate that was held down with aquarium-safe rocks. The rocks had to be placed over the holes where the up lift tubes normally are so these breeding fish could not get underneath and eat all the eggs after the spawning took place. A large clump of Java moss was also placed in beside the filter plate. The water level was down to about half of the aquarium’s volume. The temperature was 78°, pH 7.2, and the water was soft. No filtration was used, only an air stone on very low.
The five adult pearl danios were left in the 10-gallon for two days, then they were moved back to the 33-gallon community aquarium. When the filter plate was removed, the bottom of this aquarium was covered in tiny, clear eggs. These eggs are not sticky, so if some were on the filter plate they would just fall to the bottom. It took three days for all to hatch and another three days for them to become free swimming.

Feeding the Fry

As soon as the fry are free swimming they must be fed. The first food for these very tiny fry was artificial plankton rotifers, and it was fed in small quantities. Some hobbyists just sprinkle it on the top of the water, however I take a very small amount and mix it with water from the aquarium, then pour it in gently so as not to disturb the fry very much. I also do a water change every three days before I add it again. The water changes must be done with a small hand siphon in a very gentle manner so as not to pull out all of the fry. If the fry are accidentally pulled out, they can be put back in with a plastic eye dropper. It is impossible to use a net because these fry are really tiny.
With each water change, a little extra water was added so that the aquarium was full when the fry were big enough to take the flow of a filter. At about three weeks of age they were introduced to baby brine shrimp. At this point most could eat it, and those that couldn’t didn’t survive long. With baby brine shrimp being fed daily, water changes had to be done every night. Baby brine shrimp pollutes the aquarium water very quickly. Shortly after, an outside power filter of the appropriate size to fit the aquarium was added. It was set on the lowest setting, and a sponge was added to the intake tube so none of the tiny fry would get pulled in.
There were so many fry in this spawn that they were moved into a bare 66-gallon aquarium to finish growing out. Most pet stores are happy to take this fish off your hands, however I did run into a few that said they could not sell these fish because they had no color, and therefore they didn’t want them.


Since the first spawn, I have tried some different things when raising these fish. On one occasion I thought it would be interesting to breed and raise two kinds of danios in the same aquarium at the same time, but no, this does not mean cross breeding.
The breeding aquarium was set up the same way as the one mentioned above. Then D. albolineatus were added. They were left for two days, then put back into their community aquarium. I then added two pairs of leopard danios to the breeding aquarium. They were removed the next morning.
When I removed the filter plate the bottom was covered with tiny little eggs—they were literally everywhere. It took all the eggs between one and three days to hatch. This was a good indication that I had eggs from both kinds of danios. It took another four days before all were free swimming. After about a week there was a definite difference: one showed a line along the length of the body and the other fish were a beige color. At this point I wasn’t sure which ones were which. The beige color ones turned out to be the leopard danios, while the ones with the glowing line turned out the be the pearl danios. The leopard danios seemed to grow slightly faster than the pearls. Perhaps that is because the pearl danios are much more hyper, but I’m not sure.
This was quite an enjoyable experiment and quite educational as well.
On another occasion, my cories were breeding up a storm, and there were no aquariums left to raise these eggs, so I moved some of them into the 10-gallon that already contained week-old pearl danio fry. To my surprise, this actually worked! I thought that the cory eggs would fungus because the rotifers were being fed. Instead I ended up with several cory fry. Of course, with so many fry in this 10-gallon aquarium, they had to be moved to larger quarters sooner than normal. It was a good thing that some of the other fish that I was raising were ready to find new homes.
It is not a good thing to over stock the fry aquariums, after all, we are striving for strong, healthy fish. We definitely do not want to see stunted fish. In this case, I knew that the other fish would be finding new homes soon, or I would not have tried raising the cories and so many danios at all.

Try Pearl Danios

The pearl danios are a very pretty community fish that do not seem to bother any of other inhabitants. I have housed them in several different communities now and have never had a problem with any of them. The lighting has to be right or they may just look like a dull, gray fish. Remember that they will spend most of their time in the top quarter of the aquarium. The fry that were raised started breeding when they were seven months old. I kept my original five pearl danios for over two years before I gave them away. I did keep some of the fry though.

Posted May 11th, 2012.

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Where to Put Your Aquarium

Carefully evaluate the location where you want to put an aquarium before putting it there. Photograph by Leslie R. Morris.

By Leslie R. Morris

After 10 years of experience with my 55-gallon aquarium, I have learned two lessons. Lesson 1: Do not buy an aquarium that is deeper than your arm is long. Lesson 2: Except for a piano, an aquarium is the heaviest object in your home. Even new refrigerators are not very heavy compared to an aquarium.

Since water weighs about 8.35 pounds per gallon, a 55-gallon aquarium weighs 459 pounds plus the glass, rocks, and the stand. It is well over 500 pounds, or a quarter of a ton. A 125-gallon aquarium weighs over a half ton—more than 1,000 pounds.

Homes and apartments, as I learned to my dismay, are not built to support the load of a typical larger aquarium.

Builders call the dirt on which the house rests the “grade.” If your house has no basement, and the builder pours the cement floor on the dirt, it is “on grade.” If there is a basement that has a cement floor, that floor is “below grade.” If your aquarium rests on the flooring that rests on the cement, you need not worry about its weight.

When you place the aquarium on a wooden floor that is laid on wooden joists, you must be careful.

I learned this lesson the hard way. Usually, builders place stairs against a wall. My condominium’s stairs were built with railings placed on both sides. I placed the aquarium against the stairs. It was aesthetically pleasing, it did not sacrifice too much space in the room and it offered easy access to the top and back of the aquarium from the steps through the railings. However, in a few months, I noticed that the stairs were pulling loose from the floor above; I did not realize that the aquarium was the cause, but it finally dawned on me. A steel jack, installed in the basement below the center of the aquarium, solved the problem.

Where Should You Install an Aquarium?

The best place to install an aquarium is on the cement floor in the basement. Equally good is the cement first floor if you have no basement.

A house is a big wooden box that is usually designed and built by carpenters— not engineers. The strongest areas are the corners. The weakest areas are the centers of the rooms. Windows and doors subtract from a wall’s strength. Place your aquarium in a corner. If not in a corner, place it against a wall. Often, there is a steel beam in the basement equidistant from two outside walls. Site your aquarium on the floor above the beam. I wanted to place my aquarium the long way above the beam. My significant other did not want the aquarium cutting the room in half, so it straddles the beam. Every few months I check the ceiling above the aquarium to check for any separation of the walls from the ceiling. If I see any, I will install a couple of jacks in the basement.

If you use an engineer or an engineer to build your new home, tell them about the aquarium and they will build in the necessary supports.

Never Install an Aquarium Here?

I met someone who wanted to install an aquarium at the edge of the loft overlooking the living room. It is a great concept, but unless there is a steel beam supporting the edge of the loft, I predict failure.


I recently saw an ad for a large, round aquarium designed for the center of a room. It scared me. If you install an aquarium in the center of a room, install one or two jacks in the basement directly under the aquarium. Floor jacks retail for about $35.00.

The second floor of a home is a chancy place for a larger aquarium. If it is against the outside wall, it is probably okay. Apartment buildings are usually built stronger than homes. Beware of the teenager who wants several tanks in his bedroom.


Since moving an aquarium even a few feet, requires that you empty the tank and completely restart of the biological cycle, consider the initial placement of your aquarium. You do not want to relocate it.

Check the floor below for supporting beams.

Consider placing supporting jacks in the basement under the aquarium.

Monthly, check walls and ceilings for signs of separation or sagging.

Before installing your third large aquarium, consult an engineer or an architect.

Posted March 16th, 2012.

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