What is the difference between cold-water fish and tropical fish?
I believe that many people may answer like this:
"What you don't need to heat up is the cold-water fish,
Goldfish and koi are cold-water fish,
Native fish are also cold-water fish..."
This question seems simple,
In fact, it is not simple to answer
This article Xiaobian will give you a popular science:
The difference between tropical, cold-water and wide-temperature fish
What is a tropical fish?
Tropical fish, as the name suggests, is a fish that lives in the tropics, and is mainly distributed in tropical waters in Southeast Asia, Central America, South America and Africa. However, in order to distinguish them from other ornamental fish, fish farming enthusiasts collectively refer to tropical and subtropical parts of ornamental fish as tropical fish. The proportion of tropical fish in the aquarium fish market is very large, and almost 80% of the ornamental fish we can see in the aquarium ornamental fish market are tropical fish.
Common tropical fish are arowana, colorful fairy, luohan fish, peacock fish, cichlid, fighting fish and lamp fish.
01
Arowana
Dragon fish believe that many friends are not strangers, because of its long body, beard, similar to a dragon, so it is a very popular ornamental fish among the Chinese. Arowana prefers weak acidic or neutral soft water, the water temperature is above 22 °C, and the suitable temperature is 24 ~ 28 °C.
Image source: Network
Arowana has a strong sense of aggression and domain, so care should be taken to avoid homogeneous polyculture as much as possible in captivity. At the same time, the amount of food of arowana is also very large, so it is recommended that the arowana must use a stronger filtration, which is also a guarantee of water quality.
02
Colorful immortals
Colorful angelfish have very high requirements for water quality, they belong to high temperature hyperoxic fish, so the water temperature is best maintained at about 26-30 ° C, and it is not recommended to heat up or cool down sharply.
The Colorful Immortals are harsh on water quality and bait, requiring weak acidic soft water, which is difficult to survive in weak alkaline water. With a body length of about 20 cm, it can be artificially bred when mature, and males and females will bring their own fry, which is also a reason why many players especially like it.
03
Lamp fish
Many aquarists will ask, how many species of lamp fish are there?
In fact, the international general classification of such small ornamental fish into the framework of "tropical fish", there is no special "lamp family" record, so it is impossible to use scientific classification for detailed classification. The lantern fish is a group of inhabited fish, swimming among aquatic plants, with a colorful body color and very high ornamental value, and is known internationally as "a jewel that can swim".
Lamp fish are mainly distributed in Africa, the United States, Southeast Asia, the most common in the Amazon basin, the appropriate water temperature of this type of fish is between 22-28 degrees, if the water temperature at 30 degrees can avoid the occurrence of white spot disease, but if it is a grass tank, it is recommended to control at about 26 degrees, because aquatic grass in 28-30 degrees of water temperature is prone to lysozing leaves yellowing and other phenomena.
What is cold water fish?
Cold-water fish, the distribution of this fish is also very extensive, as the name suggests they can live in the water temperature is relatively low, even below 0 degrees of water temperature they can survive.
But in fact, if you are accurate to say that cold-water fish refers to fish with a maximum water temperature of no more than 20 degrees and a maximum water temperature of no more than 23 degrees, typical examples are the red-spotted salmon distributed in the European ring polar region and the golden trout on the Pacific coast of North America.
Red-spotted salmon
Red spot salmon has high requirements for the water environment, not only likes clean water quality, but also has high requirements for water temperature, and the best ambient water temperature is around 13 degrees.
Golden trout
Golden trout is a ferocious fish, when the body of the fish is very different, there will be a large fish swallowing small fish phenomenon, requiring perennial water flow, the highest can not exceed 23 degrees, the most suitable water temperature is 12 to 18 degrees, this is the real sense of cold water fish.
In general, our domestic cold-water fish are some native fish, such as the freshwater gobies we are familiar with, as well as white cloud gold wire and trout.
White cloud gold wire
The golden silk fish found near Baiyun Mountain in Guangzhou in the 1930s has another name called Baiyun Golden Silk. Baiyun gold silk is a unique fish species in China, although it can survive in the water temperature below 10 degrees, but its most suitable water temperature is between 22-26 degrees, but due to overfishing in recent years, it has been listed as a second-level key protected wild animal by the state.
04
Shrimp tiger
In addition, there are all kinds of gobies in China, and the purple goats in the streams of eastern Taiwan are very popular. The purple-skinned goby is a warm-water demersal fish with a native environment temperature of between 12 and 18 degrees, living in tropical and subtropical ravines and streams, preferring to inhabit stable water flow areas, and can also be found on rocks and stones of various sizes.
There is also a species, somewhere between tropical fish and cold-water fish, which we often call wide-temperate fish. The common butterfly carp, goldfish and koi in life actually belong to the wide temperature fish, they can survive at 5-30 degrees of water temperature, 1-5 degrees will enter a hibernating state, do not eat or swim, that is, in winter can not use heating rods is no problem. Therefore, the adaptability of wide-temperature fish is generally relatively strong.
However, it is not possible for the water temperature to fluctuate too violently. If the water temperature fluctuations are too violent, they are prone to white spot disease, so it is better to control the water temperature at about 18-28 ° C.
distinguish
Life habits are different. Cold-water fish cannot survive above 20 degrees, so they are called cold-water fish; while tropical fish can only adapt to 22 to 30 degrees of water temperature, and will die below 22 degrees for half an hour.
Origin varies. Tropical fish are born in tropical waters, but in the subtropics and in the temperate waters of the north and south at the junction with them, all ornamental fish species are also classified as tropical fish, and their distribution also includes some subtropical areas; cold-water fish are mainly distributed in china, Korea and Japan in eastern Asia.
Finally, to answer a question that many people will ask, is it possible to polyculture tropical fish and cold-water fish?