Aquaculture: Cage Culture
A new type of farming in Indiana is gaining in popularity. This farming uses water rather than water. Aquaculture, or fish farming, is the practice of raising or harvesting fish (or other aquatic life) in a controlled environment.
There are four culture systems where you can raise fish:
- Recycling Systems
Cage culture is a popular form of aquaculture that has many advantages that include resource flexibility, low cost, and simplified harvesting. This article focuses on cage culture.
Before investing any capital in a new business venture, it’s always good practice to do a thorough market analysis and develop a business plan. This will help you determine the size of the market, competition, and capital requirements. Markets are scalable from home consumption, to retail, to wholesale distribution.
After determining aquaculture farming is a viable interest for you to pursue, then the next step is to locate a body of water that will meet the biological and ecological requirements of cage culture. Lakes and quarries are possible sites. Some requirements to consider:
- Size of body of water – at least 1/2 acre, but preferably an acre of larger
- Water depth – at least 6 feet deep
- Water quality – determine pollution sources and surrounding topology
- Access to electricity – for aeration or other needs
- Access to site – by boat or vehicle
Consider the marketability of your product and your grow out site. In Indiana, tilapia is a popular fish because of its large size, rapid growth, and hardiness. Hybrid striped bass, catfish, rainbow trout, and largemouth bass are other candidates for cage culture.
Hatcheries / Fingerlings
Once you have selected your species (or species), you need to find a hatchery that can reliably provide high quality fingerlings at a fair price.
For a list of commercial suppliers, see the Indiana Dept. of Natural Resources website:
Cage size determined the number of fingerlings to purchase. You want 5 to 7 fingerlings per cubic foot. Cages come in all size, but the minimum depth should be 4 feet. Cages can be purchased or homemade. Cages range in cost from $150 to $500 per cage. The size of your fingerling will determine the mesh size you need.
Make sure you leave at least 10 feet between cages when you add them to your site. Cages must be in quiet areas (away from swimmers) and easily accessible.
The water for your cage system must contain adequate oxygen to support the fish you are growing. Natural water oxygen can be supplemented with aeration. The dissolved oxygen level and temperature of the site should be monitored closely.
Fish are shy animals and are easily subject to stress. You need to avoid stressing your fish to optimize their growth. Transport your fingerlings in a well oxygenated container.
Fish grown in cages rarely obtain enough natural food and are therefore dependent on feeds supplied by the farmers. Floating feed is the preferred feed type and hand feeding is best. Feeding the fish with the proper amount is key for optimal growth, water quality maintenance, and operational expenses.
Fish Health / Husbandry
Vigilant observation and proper fish handling techniques to reduce stress, help maintain culture conditions. Biofouling is a potential problem that can be prevented by proper maintenance. Diseases may occur from time to time. Evidence of fish disease includes skin discoloration, open wounds and lesion, fin erosions, spots, and
erratic behaviour. Seek a disease diagnosis from an accredited lab and follow the recommended prevention methods.
Fish should be harvested as soon as they reach marketable size. Make sure you minimize stress during harvesting and maintain fish in well aerated transport.
Continue your education by seeking out additional literature and by consulting with extension agents and other aquafarmers