On Sampling Biases arising from Insufficient Bottle Flushing
Collection of representative water samples using carousel bottles is important for accurately determining biological and chemical gradients. The development of more technologically advanced instrumentation and sampling apparatus causes sampling package size to increase and bottle “soak times” to decrease, increasing the probability that insufficient bottle flushing will produce biased results. Qualitative evidence from various expeditions suggest that insufficient flushing may be a problem. Here we report on multiple field experiments to better quantify the errors that can arise from insufficient bottle flushing. Our experiments suggest that soak times of more than 2 minutes are sometimes required to collect a representative sample.