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Common water quality testing instruments are as follows: Balances Balances can be said to be one of the most commonly used measuring instruments in laboratories. In particular, the most commonly used electronic balances are of various types and models, with higher precision and more comprehensive functions. In addition to weighing, they can also achieve counting and density measurement. In the field of water quality testing, the measurement of some indicators also requires the use of analytical balances with an accuracy of one ten thousandth. Choosing a reliable electronic balance can greatly improve the efficiency of water quality testing. Microscope Microscope is also one of the most commonly used instruments in the laboratory. Divided into optical microscope, electron microscope, polarized light microscope, digital microscope and so on. Generally speaking, a high-magnification biological microscope can be used for water quality testing. Biological microscopes are optical microscopes with relatively large magnifications, which can observe tiny bacteria and other substances. Ultraviolet Spectrophotometer Ultraviolet spectrophotometer is an analytical instrument based on the principle of ultraviolet-visible spectrophotometry, which uses the radiation absorption of substance molecules to the ultraviolet-visible spectral region to analyze. It is commonly used for qualitative analysis, purity inspection, structural analysis, determination of complex composition and stability constant, and reaction kinetics research. Atomic absorption spectrometer Atomic absorption spectrometer, also known as atomic absorption spectrophotometer, is used to analyze metal elements according to the effect of the atomic vapor in the ground state of the material on the absorption of characteristic radiation. It enables sensitive and reliable determination of trace or trace elements. Widely used in metallurgy, geology, mining, petroleum, light industry, agriculture, medicine, health, food and environmental monitoring and other fields. Atomic fluorescence spectrometer Atomic fluorescence spectrometer is mainly used for trace analysis of heavy metals arsenic, mercury, selenium, lead, etc. in water quality, food, dairy products, and beverages. The principle is to use potassium borohydride or sodium borohydride as reducing agent. The element to be analyzed in the sample solution is reduced to a volatile covalent gaseous hydride (or atomic vapor), which is then introduced into an atomizer with the help of a carrier gas, and atomized in an argon-hydrogen flame to form ground-state atoms.