As the Fish of the Month for March, there will a lot of Symphysodon aequifaciatus "Reflection Deep Discus" from Na Discus available at the PCS Meeting for auction. This is a special lots to raise money for Stuart Grant Fund for Cichlid Preservation and have kindly been donated by Perth Discus and Gold Coast Discus - thanks Eugene for organising this.
Symphysodon aequifasciatus "Reflection Deep Discus"
Maximum length is around 6″ (14cm). It is however claimed that Discus can actually reach 9″ in aquaria through a stringent regime of frequent, large water changes during the most important growth periods.
Order: Perciformes Family: Cichlidae
The natural range of this species extends down the Rio Solimões and along the main Amazon river, between the Rio Putamayo in Colombia and Peru as far as the Rio Tocantins drainage in Brazil. Introduced populations also exist in the neighbouring countries of Guyana and Suriname.
It’s not often seen in the main river channels, being mostly found in slow-moving tributaries and forest pools. Here it lives in schools in deep, sheltered areas around tree roots and rocks.
Wild fish feed mainly on zoplankton, insects and other small invertebrates.
Discus are carnivores, and prefer a varied diet. Most do well on a diet of frozen bloodworms, brine shrimp, as well as a good quality pelleted food. Because Discus have short guts, it is better to feed them small amounts two or three times a day rather than one large daily meal.
There were many dissections of discus in the wild. The unprocessed food was analised by Crampton, and the result is, that at the wet season 77% of the food was detrytus and plant matter, 5% were decapods, 10% Chironimidae larvae, 8% were composed of wood matter, bugs and Crustacea. In the dry season, the balance drifts towards bugs and crustacea (only 55% were composed ef the detrytus/plant matter).
Their intestines are not built for devouring the flesh of the warm-blooded animals. It’s typical for plant eaters. Given this best foods include - spirulina, spinach, peas, other vegetables, shrimps, glassworm, bloodworm, krill. No fish meat was ever found in the stomach of a wild discus.
Many Discus fanatics choose to go down the heavily planted route which can be particularly beneficial to Symphysodon aequifasciatus due to the amount of cover afforded by such a setup. Discus are very shy, skittish fish and require as much cover as possible to feel comfortable.
Although Discus only grow to around 6″, they can grow to be as tall as they are long. A breeding pair should have plenty of space both horizontally and vertically, so a tank around 48″ x 18″ x 18″ (120cm x 45cm x 45cm) – 255 litres is recommended for a few juvenile fish or a pair of breeding adults.
Regular water changes - the more frequent the better - are essential for keeping Discus in good health. They help remove dissolved organic compounds which promote poor water quality. To create the large supply of prepared water you need for frequent changes, we recommend use of a separate holding tank or aquarium equal to the size of your primary aquarium. Here you will prepare the water by removing the chlorine or chloramines, adjusting the pH and hardness to desired level, and heating the water to match the temperature in your Discus aquarium.
To prepare the water in your holding tank, we recommend a Reverse Osmosis (RO) unit to remove all hardness and toxins from the water. RO units filter out up to 99% of minerals, chemicals, and nutrients found in tap water by forcing tap water through a semi-permeable membrane. No equipment is more effective in helping create ideal water conditions.
Water Changes: Discus require the aquarium water should be changed at least 50% each week to reduce nitrates and replenish minerals. Discus are messy feeders and big contributors to nitrates in the aquarium. Be sure to dechlorinate the water before it is changed.
Nitrates should be as close to 0ppm as possible. Any reading under 20ppm is suitable for keeping Discus, elevated levels can be reduced by adding aquatic plants and removing any decaying matter.
Discus are very sensitive to any ammonia levels. There will be noticeable loss of color and heavy breathing if ammonia is present. An immediate water change is required.
Discus are highly susceptible to even very low levels of nitrite in the aquarium.
Temperature: 82-85°F (28-29°C) pH: 6.0-7.0 (as low as 5.0 for wild and breeding) Hardness: 1-4°dKH Nitrite: 0ppm Ammonia: 0ppm Nitrate: >20ppm
Just in case you didn't know Discus are part of the cichlid family, this means that they are fishes of changeable characters, personality and behavior. They can occasionally be aggressive towards their own kind and others, but generally only when pair bonds are formed or when parents are with fry. If some consideration is paid to these matters in cichlid terms they are generally fairly mild in behavior.
The main problem I find with Discus comes from bullying within their own group. Often with smaller groups of fish the individual at the bottom of the pecking order has to deal with a lot of bullying and this can lead to stress and even worse death. To avoid this the consensus seems to be that Discus should be kept in groups of no less than 4 with the optimum being 6 or more, especially when young. This seems to increase confidence in the fish and helps spread the bullying out.
Discus are social animals they live in groups in the wild and so are most at ease being kept in groups in captivity. There is more to this than simply placing a number of individuals in a tank however. Discus live in communities of individuals with a complex social order, a hierarchy of a dominant individual (usually the largest specimen) and successively less dominant individuals.
Other fishes that mix well with Discus include species that are sub-dominant and less aggressive. Aggressive fishes will outright intimidate discus into hiding, non-feeding. Faster, more-vigorous feeders will not only get to the food first, but also very likely scare your discus into isolation and lead to starvation.
Though there are many other fish species that will co-habit with Discus in terms of temperament and other aspects of behavior, I am a big fan of using animals that can be found within the Discus's natural environment. This includes a large number of "ditherfish", smaller species, mainly tetras that break up the environment, taking the discus "worries" away from their minds, as well as a few hundred species of catfishes, particularly Pleco's, armored cats and Corys.
Discus will readily reproduce in the aquarium but you may need to dedicate months, even a year (if you start out with juveniles) to the prospect. Until recently they had only successfully been bred in captivity a few times and only then by dedicated individuals. However very recently hobbyists have had widespread success breeding discuss by following a few key steps.
A Discus couple will not spawn in an aquarium that is too shallow. You will need a depth of at least 15 inches due to their tall shape. Smaller 15" cube aquariums can be used for breeding especially because they allow close contact of the breeding partners. However a deeper 36 inches x 18 inches x 18 inches aquarium would be spacious and humane for a suitable breeding pair.
Make sure the temperature is above 82 F, it needs to be a warmer climate to try and coax them into mating behavior. Replicating the summer and therefore 'rainy' climate of the amazon is a common tool in breeding aquarium fish.
The pH will need to be kept as close to 6.5 as possible and as stable as possible. The summer amazon rainstorms collect substrate and mud in the wild softening the water. The aquarium water will need to be as soft as possible from 1-4dH. Soft water has poor buffering ability hence it is important to check the water each day to ensure the parameters remain stable (especially pH). You will need to keep nitrates at a minimum by performing water changes every week and siphoning out the waste. About 30-50% will be perfect. These water changes are important and also signify breeding conditions to the breeding Discus.
When feeding breeding Discus, protein rich foods are the best choice. Diversifying food sources will help to balance the Discus diet. Professional breeders use beef heart but this should also be combined with bloodworms and vegetable matter such as spinach to aid in vitamin uptake. To keep them in good health use some high grade tropical granules twice a week to supply them with the required nutrients and vitamins they may be lacking.
Placing an upturned clay pot or cone in the discus tank will give a hard surface for the discus to lay eggs on. Be sure the surface is clean and will not pollute the aquarium. Professional plastic cones are sold on line that have been used with proven results. These may be a good consideration to increase laying chances.
Breeding Discus - Raising Young
Place the spawning medium in the center of the aquarium. The discus will spawn eggs on one side and portion of the cone. The discus will begin cleaning the medium in preparation by constantly 'sucking' at the surface.
If the discus have not visibly begun to clean the cone, recheck the water quality and ensure they are being fed consistently. It is at this stage it is imperative to ensure the water is soft. This is crucial in the formation of the eggs shell. In hard water conditions, Discus eggs can form an impenetrable shell which young cannot break. This stage is the longest of all stages and unfortunately the stage where chemistry is realized. Some discus pairs will never mate in the wild and many more will never mate in captivity. Tank bred Discus have a much higher chance of spawning when compared to wild Discus. This stage requires patience and careful monitoring.
When and if the discus spawn in this stage, they will lay eggs every week for up to fifteen weeks. This cycle usually occurs twice a year and can be rigged with careful adjustment of feeding, temperature and water conditions. This point is extremely rewarding, Discus mate for life and will hopefully continue to mate for years ahead.
After courting the eggs will then be laid on the cone or pots surface. They will be very small, mildly opaque spheres stuck to the cone in the order of thousands. The Discus will care for the eggs by constantly fanning them for aeration. The parenting Discus will even pick off and consume the unfertilized eggs to eliminate the chance of disease spreading to healthy eggs.
From this stage the eggs will hatch within 48 hours. When the eggs hatch you they do not have to be fed directly as they instinctively feed off a secretion delivered from their mother. After 48 hours they should be free swimming and growing very quickly.
Fry can stay with their parents for a lengthy period of time. However in captivity the young can become very aggressive and begin to remove scales from their mother. At the week old stage it is advisable to remove the parent Discus from the aquarium for their own safety. It is at this point it is necessary to raise the young with commercial food.
Carefully cared for discus fry can yield survival rates of up to 70%. It is recommended to only sell the Discus young when they reach at least 2" in size. This is to ensure they are strong enough for travel and acclimatization into a new aquarium.
When first introduced the the aquarium hobby wild caught Discus were a very rare sight mainly because of the belief that they were very hard not only to breed but also to just keep alive. Over time experienced hobbyists mastered the keeping alive aspect and logically the next step was to move on to breeding Discus. Slowly people managed to get their Discus to pair up and lay eggs but after moving the fry to a raising tank the fry would die within a short range of time. We now know the key is to keep the fry with their parents from whom the graze, getting all their required nutrients from their parents slime coating. Now Discus breeding is common place, providing a wide range of colors from albinos to bright blues and reds in addition to the naturally occurring wild forms.
*** Parts taken from Seriously Fish. Some of my own findings and edits thrown in.