Reply To: Mayfly Dissolved Oxygen Sensor

You might want to check out Atlas Scientific DO sensors (https://www.atlas-scientific.com/product_pages/kits/do_kit.html). They are galvanic probes that are cheap and fairly accurate (+- 0.05 mg/l), but they do require a fair bit of effort to piece together. You would need the DO kit (previous link, $280), an isolated carrier board ($40, https://www.atlas-scientific.com/product_pages/components/single_carrier_iso.html), and an extension cable where the connection to the probe needs to be waterproofed with CoaxSeal ($17,https://www.atlas-scientific.com/product_pages/components/bnc_10.html). You then would need to figure out how to connect the carrier board to the Mayfly. We are starting to use them for our project, and we’ve created our own carrier board to hold 3 sensor chips rather than use their carrier boards (https://github.com/acgold/Atlas-Scientific-Carrier-Board). They work with the ModularSensors library (in I2C mode), and the data sheets from Atlas Scientific are great (https://www.atlas-scientific.com/_files/_datasheets/_circuit/DO_EZO_Datasheet.pdf?)