The world's production of wild and farmed fish is 200 million tons. The production volume of farmed fish exceeds 110 million tons, and its presence is increasing. As the amount of natural fish caught from the ocean is decreasing, the presence of farmed fish is increasing. Land-based aquaculture has the advantage of making it easy to take preventive measures against fish diseases. In the case of marine aquaculture, the longer the period, the greater the risk of natural disasters and disease. In land-based aquaculture, if the environmental conditions such as water temperature and oxygen content are kept constant, stable shipments are possible even in the summer. For example, land-farmed salmon has the advantage of being able to be shipped year-round and providing a stable supply. Once the land-based aquaculture business gets off the ground, we can expect a stable supply of high-value-added fish such as salmon.
Land-based aquaculture has several advantages. Land-based aquaculture can produce more stable fish than natural fish, which are decreasing in the seas around Japan, and coastal aquaculture, where suitable land is limited. Attracted by this advantage, an increasing number of companies are working on land-based aquaculture. As of January 2024, there are over 660 companies involved in this aquaculture business. For land-based aquaculture, there is a "closed circulation system" in which the water in the "fish tank" is filtered and circulated. In this method, seawater passes through a layer of fine sand and becomes oxygen-free. The seawater becomes oxygen-free, making it impossible for bacteria and parasites to survive. Fish targeted for land-based aquaculture include high-quality fish such as flounder, tiger puffer, and sea grapes. On the other hand, the challenges for aquaculture management seem to be twofold: ``efforts to raise selling prices'' and ``savings on feed costs.''
There are also favorable winds blowing for land-based aquaculture. Teams from Austria's Medical University of Vienna and others have published on microplastics in the ocean. People from eight countries were surveyed: Japan, Austria, Finland, Italy, the Netherlands, Poland, Russia, and the United Kingdom. Between 50,000 and 130,000 microplastics ranging in size from 0.05 to 0.5 mm were found in all participants, regardless of country. It is believed that microplastics are introduced through food and drink. Research has not progressed enough to determine how much you need to consume to affect your health. However, its negative effects are gradually being reported. Marine pollution will continue to progress. Contaminated fish are landed. However, with land-based aquaculture, microplastics can be controlled. In terms of safety, it is in an advantageous position compared to marine aquaculture.