Marine fish actively drink sea salt water, providing the necessary level of water for normal functioning, and excess salt is removed from the body. The exchange of chlorine ions, sodium, potassium between the organism and the environment both in freshwater and marine fishes occurs through special chloride cells located in the gills, but in freshwater they are used to remove metal ions from water, and at sea to remove them from the body. This process is connected with energy expenditure, as occurs against the gradient. Energy is provided by the involvement of sodium and potassium. “Gill pump” that creates the possibility of a permanent replenishment of salts in freshwater fish, has high efficiency and is able to extract sodium and chloride ions from water millimolar and even lower concentration. Table salt since ancient times used in feed for fish as a preservative, to increase the appetite of fish, improve the absorbability, promote growth, and juvenile anadromous fish in which to prepare for the marine period of life. Due to the active exchange of sodium and chlorine with the environment, their constant intake of fish and disposal along with a large volume of liquid fish not afraid of high content of sodium chloride in the feed. Continue reading
Catfish — fish–giant. It is the largest predator that lives in fresh water. Belongs to the family somovyh. Representatives of this family are peculiar to the clumsy, highly elongated, spindle-shaped body, naked or covered with bony plates. The head is relatively large, tapered. Mouth wide, with numerous small teeth having the shape of a cone.
To this family belongs more than 550 species that live in fresh waters. Most likes deep standing water and is muddy. Catfish hunt, lying on the bottom motionless waiting for prey.
In reservoirs of Russia, the spread of ordinary som. It sometimes reaches a length of 3 m, weight 300 kg. Scientists believe that these giants are about 80-100 years, but most caught catfish weighing 10-20 kg. Their body is covered with a thick layer of mucus, the skin is dark with a greenish tint. Continue reading
These prickly predators lurk among the rocks, under the seaweed, and, like all bottom fish, change color to the color of their environment, can quickly lighten or darken depending on light conditions. Hide the Scorpion and numerous outgrowths, spikes and leathery tentacles that transforms her into one of the stones is covered with marine vegetation. Therefore, it is difficult to notice, and she relies on his “invisible” presence that floats (or rather, flies away like a bullet from a gun!) only if you approach it closely. Sometimes you can even touch – but this is exactly what not to do – that’s enough! Interesting, lying on the surface of the water and breathing through a tube, watch the Scorpion fish hunting…
The wounds from the spikes Scorpion fish cause burning pain, the injections is red and swollen, then malaise, fever, and your stay is for a day or two interrupted. If you have suffered from thorns ruff – contact your doctor. Wounds should be treated, as ordinary scratches. Continue reading