There are commercial water samplers of various brands which are available in the market. Water samples in general target obtaining water samples from desired depths without affecting its physical/chemical properties. During my graduate program at 1980s at Auburn University, USA, I have used this simple water sampler which was there in the field station. As shown in the photo, the sampler is made of a PVC pipe of appropriate length and diameter as well as a tennis ball attached to a string. Water sampling is done by lowering the closed lower end of the pipe till the desired depth and relieve the ball to allow water in before pulling the string to close the bottom end and then after pour the water into an appropriate container for sampling. This simple sampler is not substitute to commercial ones while only tells about the possibility to get the word done simply with high efficiency level.
