The silver Argos fish, also scientifically known as Selenotoca Multifasciata, whose meaning is “garbage eater,” belongs to the family of Scatophagidae (scatophagids), a family of fish that from the Animalia kingdom, of the Chordata phylum, of the Perciformes order that is distributed through both marine glasses of water and lakes and rivers of the Indian Ocean and the western Pacific Ocean.
A gregarious species follows a tendency to group to remain in a group. It does not usually exceed 20 cm in length in captivity, but if it is in the wild, this animal can reach 40 cm.
Before buying this type of fish, it is necessary to know the chemical composition of the aquarium water for sale to reproduce it in our aquarium. We can start by using freshwater for young specimens, which carry protection as a bony shield on the head and the back that diminishes over time as they become adults. During this stage, it is also essential not to place plants or seaweed around it because it will eat them unless we want to offer them as food.
However, as they grow, the salinity will have to increase to achieve a salty and spacious aquarium due to their need to form schools and swim in a wide area due to their liveliness.
Finally, due to the large size these fish can have, they can only live in community aquariums of species of origin and similar requirements and of large dimensions, that is, in marine aquariums above 400 liters that have formed the coastal areas or mangroves with many roots placed vertically.
In these natural mangroves, the salt in the water is not constant because it varies depending on the seasons of the year and the tides.
The best way to achieve good results in a brackish aquarium, that is, with a bit of salt, is that the water comprises four parts of fresh water and one part of seawater so that the density will be approximately 1.005 the pH around 7.6.
You also have to be careful with movement with aeration because this water cannot contain as much dissolved oxygen as freshwater has. However, when they are older, these pets are better in a marine aquarium with a density of between 1,020 and 1,023.
The brackish aquarium can be decorated with roots, stones, and a peripheral planting leaving enough space for swimming. A good option is rice plants. To prevent the silver argo fish from devouring the plants, you have to give them those vegetables that they like the most, trying some such as lettuce, spinach, chard, etc.
The aquatic conditions are also critical. If it is freshwater, it must be salty and alkaline water up to 8º Ph, moderately hard to tough water up to 14º Kh. And it is that these waters in which they will be found during their youthful stage have different levels of salinity throughout the day, a characteristic that allows novice fans to take practice when it comes to the chemistry of the water.
On the other hand, if it is saltwater, the suitable densities for the reef aquarium are between 1,020 and 1,024. The temperature will always be between 20 and 28ºC. Although they reside in freshwaters in their early stage and later migrate to the sea when they are adults, we can also find them in the Australian coastal area, New Guinea, and New Caledonia.
It is an omnivorous species that eat all kinds of food: Ojas, lettuce, spinach, oatmeal, cooked rice, commercial food for tropical fish as granules, sticks, and tablets, etc.
It can be offered both live food and a contribution of algae that can be given in the form of a mixture, such as Porphyra umbilicals and Porphyra yesoensis or Palmira palmitate, or it can also be given frozen food.
It should be noted that there is no apparent sexual dimorphism in Selenotoca Multifasciata and that there is no information on its reproduction in captivity. There are two theories about spawning: The first is that adults enter rivers to spawn and, when they reach maturity more or less, they go to the sea.
The second theory assumes the opposite: spawning occurs in the ocean on coral reefs, and then the fingerlings enter the rivers to grow and, when they are adults, migrate to the sea, never to return.
Regarding its appearance, it is a fish that appears to be compressed laterally, and you have to be very careful because its dorsal spines contain some poison, and it is not dangerous, but it can cause a lot of pain if you prick. Also, they have a very pointed shape.
The fins of this animal have the typical pisciform structure, with the anal and dorsal fins divided into two parts, a posterior one with soft rays and an anterior one with spiny rays.
Regarding its ventral and pectoral fins, it should be noted that they are located precisely vertically concerning each other. The dorsal fin begins vertically further back than the ventral and pectoral fins. It has 16 soft rays and 12 spines on the dorsal fin. The anal fin has four rigid spines followed by 16 soft rays.
Due to its abrupt profile, the head is separated from the body, compressed especially on the dorsal part.
The silver Argos fish has a small and horizontal mouth, not protrusible; it does not protrude and with teeth that form several rows. Their eyes are large and prominent, not excessively, and round in shape.
On the other hand, their color indeed varies according to the animal’s origin, age, and origin. Still, they are usually yellowish silver with green, olive tones, although it can also change to ocher instead of silver.
They are characterized by their dark vertical lines, black in color, which start at the back and fade and lose throughout their body until they become points of the same color, thus dominating the lower half of the body. However, this does not occur in adult fish.
The edges of this pet’s anal, dorsal, and caudal fins are also black, a color that fades over time, as is the color of the body. The neck and head of this animal have green and yellow tones.
Differentiation with other Species
Regarding how they are differentiated from other species, it is true that this pet is often confused with Scatophagus tetracanthus and with Scatophagus argus in its young phase.
However, the silver argus fish has a longer body and narrower interradial membranous fin space. The general outline of the body is hexagon-shaped, like most scatophagids.
Even so, its caudal peduncle is more extended, covering a fifth of the length of the caudal fin. Another difference lies in the pointed shape of its mouth and its large eyes.