"Observation" means the color. If the pool chlorine content is normal, the water quality is good, then the water presents bright light blue; if the waters pale, slightly cloudy, the bacteria may be exceeded.
"View" mainly refers to the water is to see the repayment is turbid. Meat see water should be clear and transparent at the bottom, standing on the side of the swimming pool through the surface can be seen the fourth lane line, if the bottom of the pond has no sediment, the pool bubble dissipated time in 15 seconds, indicating that the pool is often changed, relatively clean.
"Smell", is close to the water smell, if can smell the faint smell of chlorine, is qualified, the medicine is too thick or even choking, may be effective chlorine concentrations exceeded.
"Feeling", the water quality is soft, if feeling hard, astringent, even with the feeling of itching, the water quality may be poor.