Article in English: This is called "New Tank Syndrome", and sometimes will occur when a tank is recently set up. Many times cloudy water will disappear on its own while the water environment adjusts. Often, cloudy water is a result of mixture of microscopic organisms, such as bacteria, protozoa, and micrometazoa. These organisms come from your fish, the food, and waste. Usually, the tank will balanced out and clear up within around a week. Be patient. Before adding chemicals or trying to do anything drastic to fix the cloudy water, remember that the aquarium is full of living organisms. Figure out why the water might have become cloudy before doing anything to the water. Adding unnecessary chemicals and cleaners can upset your tank environment and harm your fish. Adding in good bacteria helps the natural processes of the tank. You can get good bacteria in the tank in a couple of ways. You can buy prepackaged bacteria from the store or buy gravel that has the bacteria already on it. You can also add gravel, rocks, driftwood, or a filter pad from an established tank to your own tank. It will have the bacteria on it.  Bacteria cultures will help to eliminate ammonia and nitrite, which are toxins. It changes them into less harmful nitrate, which is then removed during water changes. The best bacterial species to do so are Nitrosomonas and Nitrobacter.  To keep bacteria in the tank, avoid replacing the filter cartridges. Instead, wash the cartridges in old tank water. Another way you can help keep your tank clean is by adding live plants. Live plants will help reduce nitrate levels. You can buy these at your local pet store. There are different filters that do different things for your fish. Cloudy water might be due to having the wrong filter. The filter you choose depends on the density of fish, the type of aquarium you have, and  the use of live plants or artificial plants.  There are three different filters to choose from. Mechanical filters remove the particles by forcing the water through a material that catches the particles....

Summary in Vietnamese:
Chờ cho nước hết đục. Bổ sung lợi khuẩn. Trồng cây thủy sinh phù hợp trong bể cá. Xác định xem bộ lọc của bạn có thích hợp không. Suy nghĩ kỹ khi thả cá vào bể.