CATDOLL : CATDOLL: In a pond, algae multiplied in large numbers in the early stage, and the algae-eating zooplankton Daphnia multiplied in large numbers, and the algae decreased, which then caused the Daphnia to decrease. Later, sewage was discharged into the pond.

In a pond, algae multiplied in large numbers in the early stage, and the algae-eating zooplankton Daphnia multiplied in large numbers, and the algae decreased, which then caused the Daphnia to decrease. Later, sewage was discharged into the pond.

From the question, we can know that in the early stage, due to the massive reproduction of algae, the algae-eating plankton Daphnia reproduced in large numbers due to sufficient food. A large number of Daphnia preyed on a large number of algae. The algae decreased due to the increase in the number of Daphnia. When the algae decreased, the Daphnia decreased due to lack of food. This is negative feedback regulation. In the later period, water pollution caused the death of some Daphnia. The rotting corpses of Daphnia after death aggravated the degree of water pollution, leading to the death of more Daphnia. This is positive feedback regulation.

Therefore, the answer is: B.

How to Keep Windtail Fish

Anchovies are guppies

Water quality requirements for guppies

The water temperature that guppies can accept ranges from 18℃ to 34℃. If the temperature is lower than 18℃, some conditions are more likely to occur, such as loss of appetite, mental debility, and susceptibility to infection with diseases such as Saprolegnia. Therefore, whether to use a heater depends on your personal situation.

In summer, the room temperature is often higher than 30℃. In addition, the weather is hot, so the owners are usually too lazy to change the water. Therefore, the concentration of feed residues, excrement, nitrite, etc. in the water will increase rapidly, reaching the point of threatening the survival of guppies. In addition, the high temperature is accompanied by the rapid metabolic rate of guppies, which causes a large loss of calcium in the body. Therefore, large old female fish are prone to spinal curvature. The greater the curvature, the easier it is to compress the internal organs and threaten the survival of guppies. The solution to this problem is to lower the temperature. There are many ways to lower the temperature. The simplest way is to turn on the air conditioner at home. The disadvantage is that you have to bear more electricity bills. Another method is more economical, but more laborious, which is to change the water frequently. If you can change the water every day, you can reduce the temperature by a few degrees, and it can also make the peacock grow faster and the fish healthier, which can be said to kill two birds with one stone.

The most suitable pH value for guppies is between pH6.5 and pH7.5. The pH value in water has a great influence on guppies. The pH value is in logarithmic form, so water with pH5 is ten times that of pH6 and one hundred times that of pH7. Therefore, for humans, it is only a small difference of 1, but for guppies, they may be tortured to death.

Another thing to note is that if the breeder changes the water less frequently, over time, the water quality will have already become acidic due to various factors. At this time, if a large amount of water is suddenly changed, it will inevitably cause a considerable impact on the guppy.

Guppies prefer hard water, with a hardness of about 10 to 15 degrees. However, the hardness of water will not have much impact on guppies. Take Germany and Japan, two countries with a long history of raising guppies, as examples. Germany's water is hard, while Japan's water is all soft. However, these two completely different conditions can keep peacocks very well, which shows that peacocks have strong adaptability and do not require owners to bother to adjust the hardness of the water. This is one of the reasons why many people often say that guppies are easy to raise.

The level of nitrite concentration also has a considerable impact on the survival of guppies. Although peacocks adapt to nitrite concentrations much better than other fish species (according to data, the nitrite concentration that guppies can tolerate is about 100 times that of angelfish), once the nitrite concentration is too high, it is always harmful to peacocks, especially since the aquarium is a completely enclosed water body, and we usually raise fish at too high a density, so if we are careless, guppies may die collectively in a short period of time. This problem cannot be ignored. There are many reagents for testing nitrite concentrations on the market, which can easily measure the approximate value.

To solve the problem of high nitrite concentration, the quickest way is to immediately replace it with fresh, chlorinated water. However, if the nitrite concentration is too high for a long time, you must consider whether the filter is too ineffective or the fish stocking density is too high.

Guppy feed and feeding methods

Artificial feeds, there are quite a lot of types of artificial feeds on the market, which can be roughly divided into three types: 1. Flake feeds; 2. Pellet feeds; 3. Frozen feeds. These feeds are the easiest to obtain and the easiest to feed. In addition, there are feeds specially developed for guppies, which should also be the staple food of most guppy owners, and the nutritional ingredients are quite complete.

The use of live bait has always been mixed, because the nutritional value of live bait is of course far superior to artificially processed feed, but it is accompanied by safety issues. As fish owners, we must be careful, otherwise the sequelae will make you feel that it is better to just feed feed!

The safest live bait at present is probably brine shrimp (nauplii)! It does not take too long to prepare, nor does it require too many procedures. However, after hatching, you should feed the nauplii as soon as possible, because the nauplii are most nutritious when they are just hatched and still have the yolk sac. If you wait too long, the yolk will have been absorbed by the nauplii, so the nutritional value will be slightly discounted.

Another species is Daphnia, which can be bred with green water. It should be noted that it is best not to feed fish directly with Daphnia collected from the wild, because Daphnia is the intermediate host of Camelid nematodes. Once parasitized by Camelid nematodes, it is not easy to solve the problem in a few words! Moreover, Daphnia collected from the wild may have a high amount of bacteria in the wild water. If it is rashly put into the fish tank, it may infect the little baby in the greenhouse - guppy. Also, pay attention to which type of Daphnia you get. If it is a sword Daphnia, it is not suitable because of its hard shell.

Another live bait that is most commonly used in aquariums is silkworms. The nutritional value of silkworms is very high. Putting some in the fish tank can keep them alive for a long time, allowing your peacocks to keep eating, so the peacocks will grow very quickly. They can also be used as medicine bait. Feed the medicine to silkworms first to become a medicine guide, and then feed it to the peacocks. The effect is quite good. From this point of view, silkworms should be the most perfect feed, but because the source of silkworms is collected from the wild, although some aquariums will sterilize them first, no one can guarantee that the silkworms will not carry parasite eggs in their bodies, so users have to pay attention.

From the birth of the little guppy, fish lovers must be busy preparing all kinds of food. The little guppy can swim and forage soon after birth. If you find that the mother peacock is about to give birth, you can start preparing to hatch brine shrimp. Soon after the little fish is born, it will have a hearty first meal. But remember to pay attention to the amount of feeding. If too much feed is not eaten, it will pollute the water quality and cause the opposite effect. If there are no brine shrimp eggs or no hatching experience, you can also take the flake feed that is usually fed to adult fish and grind the flake feed into crumbs. The little fish can also eat it. It should be noted that the amount of bait fed should not be too much to avoid the little fish from not eating it and polluting the water quality. Another way is to use boiled egg yolks, wrap them with a net, and shake them slightly in the water. The amount does not need to be too much. Because it is too nutritious, the pollution of leftover bait will be more terrible. If necessary, you should prepare to change the water immediately after feeding.

Usually before the sex of the peacock is determined, you can feed as much high-protein food as possible. However, after the male and female fish can be raised separately, it is best not to let the male fish eat too much high-protein food to prevent the male fish's waist from becoming too thick. The female fish does not need to worry. You can feed as much as possible to make the female fish's body more rounded. However, if the feeding amount is increased, the frequency of water changes should also be adjusted relatively to avoid the water quality deteriorating too quickly, causing diseases to breed and harm the guppies. Usually mature guppies will eat all kinds of feed happily, but it should be noted that it is best not to use the same feed regularly. You can change the taste occasionally, mainly to prevent problems caused by nutritional imbalance.

Guppy breeding equipment

There is no doubt that fish tanks are a must for raising any fish. Generally speaking, except for the designs based on aquatic plants that may use fish tanks of special sizes, players who usually aim to breed guppies almost all have a considerable number of tanks. The more common ones are probably those within the range of one to two feet. Other commonly used ones include pet boxes, which are also good tools for emergencies.

If someone wants to keep peacocks for a long time and falls into the trap of peacock breeding, it is best to make a plan when setting up the tank and leave space for future expansion in advance, so that there will not be fish tanks everywhere, which will increase management troubles.

The filtration system is more important in an artificial breeding environment, because the fish tank is an extremely closed environment, and the fish's excrement is constantly accumulating in the water. If there is no way to eliminate these wastes, the peacock will definitely not grow beautiful in the long run, and may even reduce its resistance to disease. Imagine if humans lived in a place full of garbage and could not dispose of it. In the long run, how many people could bear it? Not to mention the guppies, which are more fragile than humans.

Since most guppy fish owners use many fish tanks to raise different strains of peacocks, if each tank needs to be equipped with a complete filtration system, I am afraid that not everyone can afford it. Therefore, the most common filtration method used by guppy fish owners is to use a sponge pneumatic filter, and the filter we discuss is mainly based on this. The advantages of sponge filters are: easy installation and less economic burden. And there is no need to worry that the small fish born by the mother peacock will be sucked into the filter. The disadvantage is that the sponge is more likely to be blocked and the effect will be affected. Users are better to clean it regularly, because some factors that cause diseases will remain in the filter cotton. If they are not dealt with for a long time, I am afraid that diseases will often occur.

Another commonly used type of filter is the submersible filter, which uses a motor to suck water and then uses filter cotton to filter out impurities in the water. The effect is quite good. There are also many products available on the market. You only need to clean the filter cotton regularly. It can be said to be very convenient, but the cost is too high. If you have a large number of fish tanks, I am afraid that if you use one for each tank, you will have to spend a considerable amount of money. Other filters such as top filters, cylinder filters, and even trickle filters can be used in the guppy tank as long as the filtering effect is good, but the most important thing is to fit the size of your fish tank and the budget for breeding.

Some people think that lighting is necessary for the growth of peacocks, while others disagree. However, at least there should be light to create a sense of day and night. In the dark, peacocks are less likely to accept bait; the color of peacocks will also be duller. In the presence of light, the speed of grabbing food will increase, reducing the chance of excessive residual bait polluting the water quality; the color of peacocks will also be brighter. In addition, in the presence of sufficient light, it is also easier to observe whether peacocks are infected with diseases, when to prepare to deliver small fish, and other daily routine tasks.

For some guppy players, the number of fish tanks they manage on a daily basis is so large that it is impossible to install lamps in each tank, and the electricity bill is also a considerable expense in the long run. Therefore, most of them will not be too particular about the lights, and it is enough to complete some daily work. Friends who have just started to raise peacocks do not need to spend too much on lamps.

Guppies can tolerate a wide range of temperatures, from about 18 to 30 degrees, so a temperature control system is not necessarily needed. However, if it is really hot in the summer, it is best to keep the place where the guppies are raised well ventilated. Otherwise, the temperature will be too high and it will easily cause the guppies' metabolism to be too fast. For mature female peacocks, too fast a metabolism will easily accelerate the loss of calcium in the body. If combined with postpartum disorders, spinal curvature may occur. Therefore, it is best not to let the temperature exceed 30 degrees. As for winter, because the water temperature is lowered, the peacock's growth rate slows down, which can control the growth rate of the guppies, and they will not exhaust their lives prematurely due to long-term heating.

There are also some side effects to keeping guppies living in a constant temperature. For example, they are very sensitive to changes in water temperature. As long as there is a power outage or a heater failure, it will cause considerable problems.

The bottom sand commonly used in raising peacocks should be regarded as the silica sand commonly used in aquatic plant tanks. In fact, guppies have strong adaptability, and usually there will be no problem as long as neutral bottom sand is used. Some people like to use coral sand when raising peacocks, because coral sand can make the water hard and alkaline, creating an environment that peacocks like, but you must also be careful not to let the pH quality be too high, otherwise it will have the opposite effect; if you want to plant some aquatic plants, you must consider whether you can accept this water quality. Raising guppies in a bare tank is for the purpose of breeding peacocks. Without laying bottom sand, it is convenient to change water and remove deposited feces. However, in this way, there is no bottom sand to buffer the changes in water quality. It is more suitable for friends with a little experience in fish farming, and it is best to be diligent in changing water and taking care of it, otherwise the peacock cannot live happily.