Project Overview
Commodities
- Animals: shellfish
Practices
- Animal Production: housing
- Soil Management: nutrient mineralization
Summary:
PROJECT BACKGROUND
We are a 132-acre family-owned Fish Farm with 60 ponds that cover 90 acres. For 45 years we’ve raised a variety of species including large mouth bass, small mouth bass, blue gill, fat head minnows, and crayfish for bait. For the last 5 years we also have operated the only shrimp nursery in Ohio serving some 35 growers.
PROJECT GOAL
I propose to design, engineer, and build a new nursery system that can increase shrimp juvenile production by 40 percent in the same volume of water. The new system will utilize materials that will increase the amount of substrate surface area without increasing the volume of the substrate. The increased surface area will allow for attachment of more nitrogen consuming bacteria, enabling the nitrification process to occur directly in the tank. Additionally, the design of the substrate will provide increased habitat for the juvenile shrimp, enhancing survivability.
The new system will be designed, engineered, and installed in an existing 15,000-gallon nursery tank. Shrimp juveniles will be stocked and fed multiple times daily for 60 days. Water quality parameters will be collected. During this period, shrimp will be monitored and growth, survival, and feed conversion ratios will be documented. A paper describing the new nursery system will be published in order to facilitate dissemination.
PROCESS
I have spent the past three years researching freshwater shrimp production in the U.S. I’ve visited several commercial freshwater shrimp hatcheries in Texas, Mississippi, and Kentucky. Current shrimp nursery systems are limited in their production abilities because of the type of materials they use in their culture tanks. Current systems use substrate materials, like bird netting, that do not provide much actual surface area. Additionally, because of their limited surface area, current systems require additional biofiltration to manage the nutrient load (shrimp waste and uneaten feed) and maintain optimal water quality.
I designed, engineered, and built a new nursery system that increased shrimp juvenile production by 34 percent in the same volume of water. The new system utilized materials that increased the amount of substrate surface area without increasing the volume of water. The increased surface area allowed for attachment of more nitrogen-consuming bacteria, enabling the nitrification process to occur directly in the tank. Additionally, the design of the substrate provided increased habitat for the juvenile shrimp, enhancing survivability.
The new system reduced the volume of water required to raise the juvenile shrimp which in turn will lower energy costs by reducing the amount of energy necessary to heat the water.
The new system was designed, engineered, and installed in an existing 15,000-gallon nursery tank. Shrimp juveniles were stocked and fed multiple times daily for 42 days. Water quality parameters were collected. This report paper describing the new nursery system will facilitate dissemination to other nurseries.
PEOPLE
Laura Tiu, Aquaculture Specialist at the South Centers Piketon was very instrumental in us being successful in this project. She told us about the availability of the SARE grants and helped us greatly in the grant writing process. She also provided a wealth of information and the benefit of her personal experience in shrimp culture.
RESULTS
The increase in production was 34 percent, not 40 percent as projected, but still impressive.
Survival rate was 80 percent up from 70-75percent.
200,000 PL’s were stocked and 160,000 were harvested from tank.
No water was removed from the tank. All bio-filtration happened inside the tank.
No extra water was used for back flushing bio-filters. Only water used was to make up for evaporation.
At no time did any of the water quality parameters, O2, ammonia, nitrate, nitrite, or pH exceed good levels.
Water samples were taken daily at first then weekly and tested with Hanna Ion-specific meters. Ammonia levels never exceeded .08 PPM, Nitrites did not exceed .25PPM, pH levels stayed below 8 without the need of adjustment.
Current nursery systems can typically produce around eight shrimp per gallon of water.
The objective of this project is to design and construct a new shrimp nursery system, from existing materials, that can produce up to eleven shrimp per gallon. This is an over 40 percent increase in productivity. In our 15,000-gallon nursery tank, this will enable us to raise an additional 45,000 shrimp using the same amount of water.
Utilizing this new technology, we can increase the number of juvenile shrimp produced using the same amount of water. This will help conserve water and maintain lower-cost juveniles so that the shrimp farmers that we sell to can remain profitable. Additionally, other shrimp nurseries will benefit from the transfer of this technology to their operations.
What would we do differently next time? At this point the addition of more substrate may increase production.
DISCUSSION
This was a great opportunity to put an idea into practical application. We were able to see increased productivity, and a sustainable process that will benefit the aquaculture community. The higher survival rate and lower power consumption were added benefits.
Also the main material used in this project is discarded by power companies and gives us an opportunity to recycle something that would end up in a landfill. In the process of finding markets I was able to acquire some used vegetable oil that I now use to power some of my equipment.
It has made us more productive and thereby enabled us to offer low cost juvenile shrimp to the grow out farmers. We are also able to produce a larger quantity of shrimp in the same facility so we don’t have to invest assets into expanding our nursery.
OUTREACH
Information was shared at the Ohio Aquaculture annual banquet where there were 80 attending.
Other shrimp nurseries will be encouraged to see this report on the SARE grant web page. I would be available for consultation if they would want to build similar systems.
I will be speaking at the Wisconsin aquaculture annual meeting on March 14th – 15th, 2008 on shrimp farming and will offer this info at that meeting.
I am more than willing to consult with any one that would like to implement one of these systems.