1. Sink The most suitable sinks are the following two types, glass sinks glued with resin, and plate-soluble acrylic sinks made of acrylic resin plates welded together. The size of the sink should be as large as possible and it is best to match the existing size, because it can be matched with other existing accessories. 1.45×30×302.60×30×363.75×45×454.90×45×455.120×45×456.150×45×45 2. Filter 1. Corner filter The capacity of the filter chamber is small, and it will make the water tank narrow and small. Not suitable for saltwater fish tanks. 2. Bottom filter In general sinks, a pump is used to pump water to the upper filter. After the water is filtered, it is returned to the wooden tank. There are two types of upper filters: vertical and horizontal. Their internal structures are roughly the same, but the filtering area is different. Generally speaking, the horizontal type is more ideal, and from the appearance point of view, placing the horizontal type filter on the sink is more beautiful and elegant, and it is more convenient to organize. Set up a water pipe in the sink and pass it through the bottom plate so that the water can flow downward. The method is to use a drain pipe and install a filter on the bottom of the sink. This time, a pump was set up in the lower filter, and the water was pumped upward. After the water in the mercury tank overflowed, it fell into the filter through the drain pipe. There are no merits worth mentioning about the drain-type strainer. It is just that it can be fully utilized when placed under the stand of the sink, and it is more convenient to clean the strainer. 3. The upper filter uses a motor to pump the water to the surface, and then returns to the water tank after passing through the filter bed. Special attention should be paid to the upper filter. The water flow of the motor cannot be too large, because if the water cannot stay in the filter for a while, the filtration effect will not be ideal. On the contrary, if the motor water flow is slow, the purpose of filtration cannot be achieved. 3. Filter material Coral sand is the best filter material placed in the filter chambers of the (bottom filter) and (upper filter). It has a large area and porous calcium carbonate, and nitrifying bacteria are attached to it, which can biodegrade seawater. Filtration is an indispensable and important item for raising seawater fish. The size of the coral sand is about 5 to 8 millimeters. Do not make it too fine or too large. It is best to mix it, but the difference should not be too big. 4. The heating pipe must use reliable and durable products, because if it is not of good quality in the water for a long time, it will easily cause leakage. On the other hand, the accuracy of temperature is also very important. Once, due to an error in the automatic adjustment of the heating pipe, the water temperature rose to over 35 degrees, and only one purple tango (rough-skinned sea bream) survived. If you are using a large water tank, you can place it on both sides of the tank. It is best to place it in a place with water flow, which can accelerate the flow of warm water and distribute it evenly. 5. Thermometers can be roughly divided into two types: in-water and out-of-water (attached to the surface of the tank). Personally, I prefer the in-water thermometer because it is more accurate. If you are using a large sink, you can place it on both sides of the sink. If the temperature difference between the two sides is too large, there may be a problem with the position of the heating pipe. 6. Hydrometer is a necessity for raising seawater fish. Special attention should be paid to the fact that they are thin glass tubes that are easy to break. Be careful when using them. 7. Seawater There are many different elements in seawater, some of which are important for fish. Nowadays, people who keep seawater use artificial seawater because it is clean and convenient, and the formula is also well-made and contains many elements. Therefore, many of the world’s largest aquariums also use artificial seawater. The elements in the water are absorbed by fish over a long period of time, so it is best to add some seawater elements regularly. It is recommended to raise freshwater fish first, which are also very beautiful, and then start raising seawater fish when you have experience and economy.