University of São Paulo: Most common species of ornamental fish do not adapt to round aquariums
The French company AgroBiothers Laboratoire, leader in the market of products for animals in that country, has suspended the sale of round and small-volume aquariums. According to the company, these containers shorten the life expectancy of fish and interfere with their well-being.
Although France does not have specific legislation on the subject, sales of this type of aquarium are already prohibited in other European countries, such as Germany. The ichthyology researcher at the USP Museum of Zoology, Arthur de Lima, explains that “the round aquarium is not a completely inhospitable environment, but more experienced aquarists are usually the ones who venture into this type of glass”.
According to Lima, the ban is due to the fact that the most common species of ornamental fish do not adapt to small spaces. Betta and kinguios, also known as goldfish, have high liter demands in their aquariums and rely on visual stimuli to recognize the environment, which is made difficult by the round shape of the container. “For fish that are very visual, when they see, for example, a person approaching, the image is distorted [by the aquarium] and gives the impression that it is something much bigger and that it is much closer. This can subject the fish to a situation of recurrent stress,” he says.
Another obstacle to the comfort of the fish is the great exposure to the atmosphere, which impairs the oxygenation of the aquarium and subjects the animal to pollution and contact with children or adults who can put their hands on it. “The fish itself, feeling stressed, may jump”, adds the researcher.
Responsibility and research
Aquarism is an activity that demands responsibility, and the decision to buy a fish should involve the same level of research and dedication as any other pet. “ The first step before placing the fish at home is to check if the space is adequate. If, for example, you live in an apartment and want to set up a large aquarium, you have to understand if it has the structure to be able to withstand the weight of the water. If you want to put the aquarium inside your room, you need to see how much light and airflow it is getting.” Lima points out that such measures are important to even avoid accidents and aquarium breakage. “The level of commitment should be as high as you can get without interfering with your routine.”
For beginner aquarists, the researcher recommends starting with medium-sized aquariums, with a liter of between 40 and 50. Knowing the pH of the water in your city or neighborhood will also be important, since it directly affects the physiological processes of the fish: some species they adapt better to acidic waters, and others, to crystalline ones.
In addition, the aquarium must be equipped with filters, thermostats, thermometers and some chemical reagents to regulate and monitor the pH. “I personally like to buy an ammonia meter too. Fish are animals that excrete the substance, which is highly toxic and accumulates in the water. Therefore, from time to time, depending on the water content of your aquarium and the flow rate of your filter, you need to perform a partial water change”, concludes Lima.