Recirculating Production Pond Inflows to Increase Production and Reduce Effluents on Small-Scale Fish Farms

View the project final report

• 2004 annual report
• 2005 annual report

Commodities

• Fruits: berries (other)
• Animals: fish

Practices

• Animal Production: manure management
• Crop Production: nutrient cycling, organic fertilizers
• Education and Training: demonstration, on-farm/ranch research
• Farm Business Management: new enterprise development, budgets/cost and returns, feasibility study
• Sustainable Communities: sustainability measures

With guidance from University personnel and funding assistance from SARE, the cooperating farmer has had the opportunity to explore the economics of recirculating water through his multi-pond production system. Recycling this water along with integrating secondary non-fish crops has helped reduce the amount of potentially nutrient rich effluents leaving the farm and allowed the farmer to increase his productivity and efficiency.

While all of the pre-determined objectives for this project were met the overall results were less than we had hoped. A number of difficulties were encountered throughout the process. There were two major factors affecting the project. First, and most difficult to manage was the weather. Over the course of the experimentation period the farm was subjected to three hurricanes and several other major weather events, including hale. This adverse weather all but ruined several crops, including both the aquaponics and terrestrial vegetables. The other major factor was the health of the farmer and his labor force. Both the farmer and the primary laborer on this project had serious health difficulties during the project. These issues prevented optimal management of the project and restricted the anticipated intensification of production in both the fish and plants arenas.

Introduction

While there are vast water resources in the Piedmont region of Alabama, only a small percentage of these water resources are being used by farmers to grow fish. Most fish farms that are outside of the major production areas such as those in East Alabama are relatively small and require diversification and/or maximum use of their on-farm resources in order to remain viable. Small farms with limited acreage are getting squeezed out by large scale industrial farms

Some fish farmers have access to spring water and flowing streams that can be used to intensify production and help them remain competitive. However, most farmers with spring water input have traditional water storage ponds (deeper than 10 feet) and much of this spring water is underutilized or just flows over the spillway. Several farmers, in an effort to further utilize this flowing water have built earthen raceways below their water storage ponds where they grow catfish and other species. This flowing water, along with aeration has allowed them to intensify their operations and help them remain competitive. One farmer has shown interest in recirculating this water back through the pond systems to "filter" it for reuse and to reduce the water effluents from the farm and possibly integrate some secondary non-fish crops in the process.

Objectives for the first year of the project included.

Installing pumps and piping
Preparing, planting and maintaining new garden plots
Constructing aquaponic rafts for use in the ponds
Stocking fish
Measuring baseline and ongoing water quality data
Recording progress

These objectives were successfully accomplished and with the exception of most of the aquaponic rafts (along with the plants) being destroyed by hurricane weather the other objectives appear to be progressing as expected. The quality of the effluent leaving the farm was well within acceptable limits and there did not appear to be a significant build up of nutrients in the ponds. With the many variable associated with this complex environmental system the direct impact of the water recirculation and additional plant production are difficult to establish.
The objectives for year two included:

Preparing the garden plots. Completing the harvest sorting and marketing of year 1 fish from raceways. Restocking the raceways with catfish. Preparing/repairing the aquaponic rafts and germinating seedlings. Feed fish and monitor their growth. Monitoring and maintaining water quality. Planting and maintaining aquaponic plant rafts. Harvest fish and plants and record the profits and losses associated with the project.