A critical part of an aquaculture operation is feeding the fish the right amount of food at the right rate at the right time, and monitoring this operation and the environmental conditions at the site. The UNH Open Ocean Aquaculture demonstration project is working on its third automated, remote feeding buoy for offshore aquaculture. A central part of the buoys is the control system, consisting of (1) a computer and software in the feed buoy controlling operations, (2) the two-way telemetry link between the offshore buoy and shore station with its supporting computers and Internet links back to UNH and the (3) the user friendly interface at a control center.All the activities monitored by the controller in the feed buoy are stored in files each hour in the buoy to document what has happened. These files are relayed hourly to shore by a 900 MHz spread spectrum telemetry link. When this data is received on shore it is stored on a computer, and at regular intervals sent to the UNH campus for archiving and study. Also, the real-time data is relayed via an internet link to the control center, so that the current drawn, amount of feed supplied, etc. can be monitored. New files that control the timing of activities and control an activity can be created at the control center to alter a programmed activity based on observations of the offshore system status. These files are automatically sent to the coastal shore station and relayed to the feed buoy at the start of the next hour's cycle. Thus, feed buoy activities can be regularly altered in response to monitoring of the fish. The system also monitors such environmental quantities as the depth of the cage with a pressure sensor and the temperature of the water at three depths in the fish cage to warn if it is too warm for the fish, and thus provide a record of the environment around the fish.A system of video cameras in the fish cage observes the fish before, during and after feeding to evaluate the feeding program and fish activity. The video images are captured, compressed, and telemetered to shore to the control center. While the 900 MHz link can handle the routine transfer of data and files, this link is not able to provide the continuous real-time images desired by operations managers. A 2.4 GHz radio utilizing 802.11b protocol with a 24 db gain antenna on shore could not reliably telemeter data the 7.5 nm from the buoy to shore.The third feed buoy is evolving using all of the previously learned knowledge and incorporating several new technologies that will aid in the difficult task of offshore aquaculture. Most This work was funded by the National Oceanic and Atmospheric Administration under Grant NAO40AR4600155.importantly, new telemetry equipment that utilizes the current 900 MHz spread spectrum band at higher bandwidth will yield a robust communications package that will allow for better control and monitoring of the offshore feed systems.

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A critical part of an aquaculture operation is feeding the fish (at the right time, the right amount at the right rate) and monitoring the operation. The UNH Open Ocean Aquaculture demonstration project is working on its third and most ambitious automated, remote feeding buoy for offshore aquaculture operations. A central part of the feeders is a computer and software in the feed buoy, which controls and monitors the operations. This onboard processor has a large variety of tasks. It must start the generator in time for scheduled large power drain activities such as powering lights in the submerged fish cages to delay sexual maturation, and the feeding operations with its pumps, feed augers, feed dosers, etc. Also, the system must monitor of the status of each of these activity as they are taking place. This includes seeing that the generator started properly, that power is on the generator's power bus, and then switching it to the main system power bus. When activities such as feeding are taking place, the system must monitor the quantity of feed in the feed hopper, the rate that the feed is being delivered to the feed hose, and the pressure in the feed hose (to catch any blockages). The system also has a series of critical points that it monitors, such as any water in the buoy, the backup battery voltage, the rate of charge by any solar and wind power system and any critical problems with feeding or other activities. The system is programmed to respond to any problems, such as emergency shut down of the generator should it get too hot, the oil pressure too low, and the fuel level gets low. It will also terminate any feeding activity if the pressure in the feed hose rises indicating blockage. If water is detected in the buoy, indicating a leakage in the buoy itself or from one of the subsystems, the system sends an alert to shore as well as turns off any critical activities and making sure that all bilge pumps are active.The programmed activities are controlled by a series of files stored on compact flash in the computer. The system checks each hour to see if an activity is scheduled, then reads another control file (listed in the activities timing file) that will control the details of that activity. If it is feeding time, then it will read the feeding file specified which will tell how fast to feed, for what duration, and what sequence of pumps to use during the feeding process. By referring to different feeding control files, several feeding schedules can be run during one day, or on a weekly cycle. A feeding cycle may include putting a small amount of feed in the hose, then turning on a pump to wash it down to the fish cage, then waiting a little time for the fish to eat that food, and repeating the operation a number of times again. These systems are evolving with the third feed buoy, and lessons learned from the first two are being incorporated into the next.