In the near future, likely within the next fifty years, the first human colony (or colonies) in space will be established. In the news, most of the issues you hear about with regards to space colonization are concerned with transportation, lack of sufficient gravity, or radiation. While these are certainly issues, they are just the tip of the iceberg when it comes to the hurdles of building a sustainable human settlement beyond Earth.
Efficiency is going to be extremely important in early space colonies in order to minimize costs and optimize the human habitation areas. One of the most effective ways to create an efficient nutrition system for the colonists is aquaponics. Aquaponics is the idea that you can create a closed, water-based system of plants and animals that can be used as a food source. The plants grow without soil, and they gain the majority of their nutrients from the excrements of the fish, shellfish, and other aquatic creatures living in the water below. These fish excrements are a very good source of fertilizer, but the plants’ nutrients can also be supplemented by any man-made fertilizers the colonists have on hand if needed.
An aquaponics system would be effective for a number of reasons. Most importantly, they can grow a large variety of plants that could provide healthy sources of nutrition for the colonists. In particular, leafy greens like lettuce, cabbage, and spinach excel in an aquaponic growth system. The fish are the other important component of the system; they can be both a source of food for both the colonists and the plants. Additionally, the water in the system would be recycled for the colonists to drink and then recovered from the colonists’ waste, purified, and reentered into the system.
NASA is well-aware of the concept of aquaponics. They even received an aquaponics project from a high school once as an entry to one of their science contests. However, creating an aquaponic system on a foreign world like the Moon or Mars will be a challenge. There’s no way of knowing how the various aquatic species will react to space travel. There’s also the danger of one disease killing off the entire fish and/or plant population at once since the system is fully integrated. Colonies would likely want to get multiple, separate systems as soon as possible in order to minimize this possibility.
Still, aquaponics checks off all the boxes when it comes to space nutrition. Aquaponic systems could provide both vitamins and protein. They could be custom fit to containers and stacked vertically in UV-lit rooms in order to maximize space usage. They would be mostly self-sustaining, so fewer colonists would be needed to tend to them. The systems could also be monitored by computer equipment to ensure nutrient levels in the water are maintained. These potential aquaponic systems are sure to prove greatly beneficial for future space colonists.