Ease of handling each task
Human nature is the one factor the farm or RAS designer cannot control; humans are by nature lazy and we take the shortest route every time. A new system normally runs beautifully as designed, unfortunately a month or two later the same system will need a huge amount of maintenance and cleaning.
For example; saving on money by using stone or sand in a large filter system instead of lighter materials available at a higher cost, might seem financially wise but the long-term consequences soon catch-up. The labour needed to clean large filter systems like this is huge and will not be done perfectly; bacteria would die off leaving the system with suboptimal conditions. These tasks are often neglected because they are too difficult. A moving bed filter cost 5 times the price but is self-cleaning, removing the human factor is always going to be a win without compromising water quality.
Every task on the farm has a human element, make each task easy to complete accurately without harming the equipment or compromising quality or fish safety. Harvesting, water tests, breeding, heating, cleaning, maintaining and husbandry need to be jobs that you make as easy as possible or they will suffer some form of neglect.
Introducing a parasite, pathogen or disease will set back the entire operation by months or years, if not permanently. Some viral disease can remain dormant in an aquaculture system indefinitely and become almost impossible to eradicate without completely fallowing, dismantling and disinfecting the whole system.
Damage to a farm reputation with an outbreak of a serious viral disease like Tilapia Lake Virus or bacterial Streptococcus can be difficult to recover from, therefore get professional help from the start of the design.
Incorporating the help of a qualified fish veterinarian is the only safe way to ensure complete biosecurity. The same vet could be asked to vouch for the biosecurity when new stock might be brought into the country or if the produce needs a certificate for retail or export. Retrofitting biosecurity can be a difficult and expensive exercise.
Last but most importantly aquaculture needs to be seen as a sustainable and environmentally responsible exercise. Aquaculture farmers need to be seen as humane breeders and growers with respect for the environment and fish welfare, from the start of the life cycle to the end of the life cycle. There needs to be responsible management of water. Each farmer and labourer represents the Tilapia industry in South Africa and we have a responsibility towards each other.