An aquaponic system isn’t difficult to maintain but there are daily and periodic tasks that must be done to ensure a healthy system.
The availability of dry, species-specific fish food is quite new and is the result of the rapidly growing aquaculture industry. Today’s specialized fish feeds provide precise amounts of protein, carbohydrates, fats, vitamins, amino acids and minerals. In a hobby or ornamental system it is fine to feed your fish only once a day. If food production is your goal, you’ll want to maximize your efforts and feed more frequently. Most commercial growers will feed three times per day. Feeding by hand gives you the opportunity to observe the fish and their feeding habits. You can also use timed mechanical feeder or use an on-demand feeder so the fish can eat whenever they are hungry.
Plant Seeding, Rotation and Harvesting
When growing leafy crops that quickly mature, such as lettuce and herbs, you should plant frequently so you are assured of a continual harvest. With leafy crops, when you havest, you seed and transplant the same number of plants you harvest. This will provide continuous harvests.
Indeterminate varieties of many long term crops, tomatoes and melons, can produce for many months.
Seeds for an aquaponic system are usually germinated in a small rockwool cube or in a container of loose perlite, vermiculite, a seedling mix or coco coir. Germination can be done within the aquaponic system or in a separate area designed to provide proper environmental conditions for germination. Once the seed has germinated and a seedling has developed, the small plant is transplanted into the plant bed.
Observation and Monitoring
Every day you should visually inspect the fish and the system. Make sure the water is flowing properly, the aeration system is working and the drains are free of debris. Watch to see that the fish eat vigorously and swim normally. Look for problems such as fungus, open soars, torn fins or discoloration and check the temperature and pH of the water. Observe the plants for pests and insects. Remove any dead plant matter.
In a home food production system, you will most likely harvest fish as you want them, once they’ve matured. Commercial operations will harvest based on market demand and production. Farm raised fish always taste the best if they’ve been purged for several days prior to harvesting. Ideally, the fish should be removed from the main system and held without feed for several days prior to harvest.
Water Quality Testing
Anyone serious about aquaponics should invest in a water test kit, which will enable you to measure and keep track of pH, ammonia, nitrite, nitrate, dissolved oxygen, alkalinity and water hardness. Most kits sold are easy to use and are based on color changes in the sample being tested. Meters that measure dissolved oxygen, temperature and other factors are also available.
Cleaning Filters and System
The key to a healthy system is keeping it clean, removing any dead or unhealthy plants or fish, maintaining filters and emptying the clarifier if you are using one.