General heating rods are divided into glass and stainless steel, glass heating rods are inexpensive, use a wide range, can be used in a variety of fish tanks, but the disadvantage is relatively easy to break, intolerance, in some large fish tanks If a glass heating rod is used, it must be equipped with a protective cover. This is done so as not to damage the fish. The other is a stainless steel heating rod, its advantages are obvious, the outside is strong and durable, not easy to be broken, the appearance looks more texture, but the disadvantage is that if it is used in a corrosive environment is not possible, For example in a seawater tank.
At present, there are mainly two types of heating rods that are popular in the market. The specific usage of these two types of structures and some usage matters are described in detail below.
The first is to directly control the temperature with a bimetal. Simply put, a bimetal is placed inside the heater. Since the two sides of the bimetal are made of different materials, the coefficients of thermal expansion are different. This can be used. Automatically disconnected when it reaches the temperature you set. The advantages are simple structure, low price and high working reliability. The difference between a regular factory and fake and shoddy goods is a large part of this place. The counterfeit goods are poor quality products. After a certain period of use, they are prone to fatigue, causing the temperature to be set to not jump off, and thus causing Irreversible result. The disadvantage is that no matter what kind of material bimetal, there will be an aging period, so I suggest you can change one in 2 years.