HI 9147 Dissolved Oxygen Meter for Aquaculture HI 9147 is designed for aquaculture applications. This unit is unique among our family of DO meters as it is supplied with a galvanic probe. Unlike polarographic probes, galvanic DO probes require no conditioning time. When you need to measure multiple samples in a given period of time, pick it up and measure on demand. HI 9147 ... Read More »