Tropical Aquarium Fish

If the dream of any experienced aquarium fish breeder is to have in his/her aquariums at least 2 discuses, the dream of a beginner breeder is to have at least 2 scalars. The first aquarium will be populated with a big variety of fish and the scalars won`t be absent. The spreading area is between the middle Amazon areas, north area of South America, Guyana and Orinoco area. It`s a round body fish, sharp mouth, very flattened. It looks more high than long, because of its dorsal and anal fins which are very remarkable. The background is colored in shining silvery. The length is about 15 cm and the height is 25 cm (for veiled forms, these sizes are over fulfilled). The forehead is a little convex, the back and scruff are brown to olive and the abdominal area has blue iridescence. Most of the times it has 4 lateral and vertical lines colored in dark blue which are organized like this:
- the first one crosses the eye and reaches the neck
- the 2nd one starts under the first rays of the dorsal fin and reaches the anus
- the 3rd one, the widest, starts from the upper end of the dorsal fin end ends exactly near the low end of the anal fin
- the 4th one covers the base of the tail (till the start of the caudal fin rays).
In the spaces between these lines some other lines more or less colored can appear, and sometimes even the 4 main lines can be absent. The breeding temperature is about 24° C, and in the reproduction period it needs 26-28° C.

P. scalare is relatively easy to breed in the aquarium, although one of the results of generations of inbreeding is that many breeds have almost completely lost their rearing instincts resulting in the tendency of the parents to eat their young. In addition, it is very difficult to accurately identify the gender of any individual until they are nearly ready to breed.

Angelfish pairs form long-term relationships where each individual will protect the other from threats and potential suitors. Upon the death or removal of one of the mated pair, some breeders have experienced a total refusal of the other mate to pair up with any other angelfish; others have had more success with subsequent mates. Both parents care for the young.

Depending upon aquarium conditions, P. scalare reaches sexual maturity at the age of six to twelve months or more. In situations where the eggs are removed from the aquarium immediately after spawning, the pair is capable of spawning every seven to ten days. Around the age of approximately three years, spawning frequency will decrease and eventually cease.

When the pair is ready to spawn, the pair will choose an appropriate medium upon which to lay the eggs and spend one to two days picking off detritus and algae from the surface. This medium may be a broad-leaf plant in the aquarium, a flat surface such as a piece of slate placed vertically in the aquarium, a length of pipe, or even the glass sides of the aquarium. The female will deposit a line of eggs on the spawning substrate, followed by the male who will fertilize the eggs. This process will repeat itself until there are a total of 100-600 eggs. The pair will take turns maintaining a high rate of water circulation around the eggs by swimming very close to the eggs and fanning the eggs with their lateral fins. In a few days, the eggs will hatch and the fry will remain attached to the spawning substrate. During this period, the fry will not eat and will survive by consuming the remains of their yolk sacs. At one week, the fry will detach and become free-swimming. Successful parents will keep close watch on the eggs until they become free-swimming. Once they begin swimming, the parents will clean them by sucking them into their mouths and spitting them out. At the free-swimming stage, the fry can be fed newly-hatched brine shrimp ; frozen or fresh.

P. altum is notably difficult to breed in an aquarium environment.

Every fish breeder dreams to having an aquarium with discuses, to being able of breeding even reproducing discuses. This superb fish, from every point of view: shape, size, color, behavior, represents the top of pride in our aquariums, pride top which most of times we can`t reach. For being able to breed this fish, we need more years aquaria experience, and theoretical knowledge that most of us don`t have. It`s not enough to have an aquarium, water, aquatic plants, a vibrator and maybe a heater in order to buy two or four discuses and claim that we are discus breeders. We can`t say we are discus breeders even if we have discuses in our aquariums The literature about Symphysodon discus has improved in the last 10-15 years, but most of the aquarium fish breeders don`t have access to it, same thing happening with other aquarium fish species too. In Romania there are some breeders, also in Bucharest, who reproduce this fish regularly, which used to have a methodic price before the revolution (anyone could afford buying it). But let`s get back to the requests of breeding discuses, requests that are very important to fulfill. Of course we need an aquarium (but not any kind of aquarium), water (but not any kind of water) and temperature (but not as for other aquarium fish species, discuses need a constant temperature maintained at 28-31° C using a thermostat). Why do the discuses need such a special care, different than any other species? What are the differences between discuses and other aquarium fish, even those from the same natural habit?

The discus is a fish which has a continuity of only 50-60 years in our aquariums; I`m talking about the wild discuses. The reproduction is not as hard as the fulfill of the needed conditions. These conditions are the same as in the natural environment. The fry care is a big difference between discuses and any other aquarium fish. Everything is special with discuses: from food to water, spawning, diseases (some diseases are specific only for discuses). So let`s see what we know about discuses.

There are two ways to go about obtaining a breeding pair of discus. The most common is to buy a group of young discus and grow them up together. For a good chance of getting a pair, at least six discus must be purchased, hopefully from a few different sources so as to get some genetic diversity in the breeding program. These fish are then housed together until pairs can be determined. When two discus pair off they will defend a territory in the aquarium against all of their other tank mates. When this behaviour is observed it is time for the breeder to move the “newlyweds” to an aquarium of their own. The second way to obtain a breeding pair is to go out and buy one. This is a more expensive route, since proven pairs sell for several hundred dollars, but it will yield the fastest results.

Regardless of how you get your pair, you will need an aquarium set up for them with the objective of breeding in mind. A twenty or twenty-seven gallon tall tank is ideal for these “tall” fish. The bottom is left bare, so that removing any left over food and other debris is easy. The only decor required by the pair is a spawning surface. Discus lay their eggs in the same manner as angels, and so a vertical surface should be provided for them to deposit their eggs on. I use an inverted ceramic flower pot, but the discus aren’t picky and will use whatever surface is available. A potted plant or two can be added to the breeding tank if so desired, and will provide some shelter for the pair, but this is not essential. As far as filtration goes, a sponge filter should be used to handle the biological load, and an outside power filter to pick up any debris that may be in the water. I also like to add a mesh bag of peat moss in the power filter so as to better replicate the natural water conditions that discus come from.

This brings us to the first and most important secret you will need to know if you are going to have any success breeding discus. This is the secret of water quality. Discus come from the warm, soft, acidic waters of the Amazon River. It’s no surprise then that discus thrive when these conditions are replicated in the home aquarium. For both general maintenance and breeding of discus the pH should be kept at 6.5, and the temperature around 86 F. Any alterations that need to be made to the water chemistry should always be done prior to the water being added to the tank. For general maintenance water changes should be performed weekly. However in the breeding tank, a small water change should be done every day, or every second day. Frequent water changes increase appetite and promote mating activity in discus. It’s no coincidence that discus will often spawn after a water change.

The second secret is related to the first, and this is the secret of food. If good water quality is maintained the discus will have large appetites and should greedily accept any food offered to them. My discus get fed only frozen bloodworms. The reason for this is that they are clean and convenient to use. Other foods that can be used include beef heart, Tetra Color Bits, frozen or live brine shrimp, and live white worms. If feeding beef heart, one must be careful that none is left over because it will foul the water very quickly. Live tubifex or black worms should never be fed to discus at any time, as I can guarantee that they will introduce parasites to the tank.

Once these two secrets are mastered, breeding discus is a cinch. The breeding pair will lay eggs as often as every week, as many as fifteen times. They will usually go through two of these spawning cycles in a year. The eggs take 48 hours to hatch , and are free-swimming another 72 hours later. Immediately upon becoming free-swimming the fry will move to their parents’ sides, and start feeding off the mucous secretion that is produced by the parents during this time. The fry will feed off their parents’ sides for as long as you leave them together, but they should be offered newly hatched brine shrimp after being free-swimming for five days.

The natural habit is in South America in middle Amazon area, Rio Plata, in stagnant waters or with slow flow, with rich vegetation, with plenty of rocks and roots. From the behavior point of view they are similar to scalars, with which they are friendly. It doesn`t need special foods; it eats almost anything, even dry food as flakes or tablets. It needs a supply of vegetal food, or the given tablets should contain vegetal parts too. The optimal temperature is about 25° C and for reproduction it needs 26-27° C. It has some water chemistry preferences, needing a pH of 6.5-7 and 5-8° dGH. In aquariums it appreciates the sunny areas, but shadowy ones aren`t bad either. It likes rich planted aquariums.

The body shape is typical to Cichlids, so it has a burly body, laterally oblate, with a big sharp head and a small mouth. The fins are imposing, the anal and caudal are sharp, the abdominals are prolonged and the tail is round. It can reach 15 cm length.

The body is colored in yellow-grey to green-grey; the back is olive-brown, the pectoral area is blue-green. On the body laterals it has a line from the mouth to the base of the tail which divides the body into two different colored areas. It can also have some lateral transversal lines made from dark colored spots. At the base of the tail it has a black spot with light colored outline. The fins are colored from yellow-grey to blue.

The sexual difference isn`t obvious, both the female and male are colored the same. As in the scalars case, the sexual difference can be observed in the spawning period, looking to the genital pupil. The male`s is shorter and sharp at the top, and the female`s is larger with a cone trunk shape. In general the male is bigger; it has sharp anal and caudal fins, while the female`s are round.

They are friendly fish, sheepish and timid, they don`t grout, and they don`t attack the plants (if they are fed with vegetal food). They need large aquariums. They are sensitive to old water, that`s why we have to change the water regularly. For reproduction, it`s better to let them pair themselves. In order to do that, there has to be more youngsters in the aquarium. One of the maturity signs is the red iris, as for scalars. The fry hatch after 48 hours and swim free after 8 days. When they swim free we`ll feed them with Artemia salina, micro worms or small daphnia. The fry grow quite fast.

The origin of Cichlids family is very old, dating from before the continent’s split. It contains over 1000 species of fish, with different behavior, body shape and colors. The fish are spread over large tropical and subtropical large area, avoiding the cold and temperate areas. So you can find Cichlids over Africa, some areas in Small Asia, south coasts of India, Sri Lanka, South and Central America. There are some geographical areas where the Cichlids are grouped in a large number. We can enumerate the big lakes from East of Africa: Malawi, Victoria, Tanganika, Congo River area, the tropical area of West Africa and Congo to Nigeria. In South America these groups can be found in Amazon River area and in Orinoco River area. Practically, in Africa, the Cichlids can be found everywhere, even in Madagascar.

From the feeding point of view, Cichlids prefer the bottom of the water because here they can find mosquito or other larva, hidden in the deposed mud under the leaves. Theserva represents their main category of food. If you are interested on the way they find their food, you can find detailed info at the Symphysodon discus chapter.From the reproduction point of view, they also prefer the bottom of the water because there they can find flat rocks on which they spawn. Regardless of the way they hatch their eggs, in the mouth or normally, the spawning always takes place on flat rock or on plants with flat leaves. Cichlidae fish have a much evolved way of spawning, that’s why they look for the safest place where to do it, or they dig up holes in the ground. For spawning, they prefer places with clean and calm water. Some Cichlids look for sunny areas in order to help the hatching. Also, in clean water, the fry can find small foods and protection.

From the hatching point of view, there are 2 kinds of Cichlids:
- Cichlids which hatch their eggs in the mouth
- Cichlids with normal hatching, on the flat plant or rock where the parents spawned.
The Hatching is strictly protected by the parents.

From the coloration point of view, Cichlids have varied colors and drawings. So some species are rich colored and some have poor colors, some have very complicated drawings and some have just a few uncolored spots or lines. The colors and lines can change from a second to another, depending on the feeling of the fish. This way, the transversal lines can appear or disappear (for Discus). In the first weeks, the offspring is colored different than the parents; some have lateral signalization spots, maybe in order to be recognized easier by the parents. In nature, this fact can save them from the bigger fish, because they can black out. Some Chiclids change their colors few times till they grow up. The definitive colors and drawing comes only when they are sexually mature. Sometimes the colors are so different than the parent’s that a beginner breeder can’t even find out the specie of a fish. The fish have different colors and drawings depending on the different situations:
- for impressing the female
- for threatening
- for fighting
- for spawn care
- for reproduction care
A wired thing is that a defeated male can take the colors of a female. The coloration from the reproduction period is usually different than any other period, some new colors can appear. The male colors are different than the female’s, but there are some exception: scalars and discuses.