• Dissolved Oxygen must be within a range that supports sea life. Unusually low dissolved oxygen around the aquaculture installation indicates that its presence is impacting the surrounding water. Furthermore, low or anoxic conditions resulting from upwelling or eutrophication can lead to massive mortality events.
• pH – ocean acidification is of particular concern to shellfish aquaculture but will also affect fish stocks. Monitoring long-term trends of pH as well as discrete events is crucial for detecting and mitigating potentially catastrophic impacts.
• CTD Data, including water temperature and salinity – All species thrive in an ideal range of ocean conditions. Some species thrive in warmer brackish water, while others prefer cold open ocean pens. Measuring CTD data allows operators to select a plot within the bounds of the appropriate environmental ranges, while tracking changes such as helps to predict events such as harmful algal blooms.
• Loading of nutrients such as Nitrate and Phosphate can cause eutrophication, the rapid algal growth that leads to low oxygen. Understanding potential sources of nutrients from artificial sources can inform decisions on aquaculture plot locations.
• Chlorophyll concentration and irradiation provide an estimate of photosynthetic biomass and primary productivity, i.e. the bottom of the food chain. Low chlorophyll concentration may indicate potential impacts to the food chain, which high chlorophyll concentration may indicate artificial nutrient loading or the presence of a harmful algal bloom.

• Other environmental baseline measures include current speed and direction, air temperature and pressure, wind, and precipitation.

• Harmful Algal Blooms (HABs) pose both a physical and chemical threat to fish and shellfish farms. Serious HABs can clog fish gills and introduce toxic chemicals into the food chain. Autonomous sensors can provide data for advance modeling and prediction of HABs.
• Eutrophication, often from runoff, can lead to anoxic conditions inhospitable to aquaculture.
• Ocean Acidification - for the shellfish industry, ocean acidification is a constant threat. Plots of juvenile shellfish (referred to as “seeds”) can be decimated by a single low-pH event. Some shellfish farmers in the Pacific Coast have had to move operations to Hawaii due to corrosive waters on the mainland, with limited success. As the environment changes, an understanding of environmental baselines becomes crucial knowledge for a successful operation.
• Disease from highly concentrated plots and insufficient biosecurity measures.

• HydroCAT-EP V2 Multiparameter Probe– measures temperature, conductivity, pressure, dissolved oxygen, pH, chlorophyll, and turbidity in a single package. Designed for long-term deployments on moorings.
• 37-SMP-ODO CTD and Dissolved Oxygen sensor – an oceanographic staple, measures temperature, conductivity, pressure, and dissolved oxygen in a robust package with internal memory and real-time output.
• SeaFET/SeapHOx V2 ISFET pH and CTD + Dissolved Oxygen Sensor– ISFTET pH sensor with optional CTD and dissolved oxygen sensor, designed to withstand harsh conditions and provide highly accurate and stable pH for several months.
• ECO Combination Optical Sensors measure chlorophyll, turbidity, and backscattering.
• 39plus Temperature and Pressure Logger– robust and reliable temperature and optional pressure sensor with internal logging and real-time output.
• SBE 56 Miniature Temperature Logger - compact and reliable temperature sensor with internal logging
• SUNA V2 Nitrate Sensor– utilizes optical UV technology for long-term high-resolution nitrate measurements without wet chemistry,
• PAR Sensors measure photosynthetically active radiation.