Greenhouses are not strictly required for successful aquaponics, but they do offer some definite benefits. If you’re starting up an aquaponics project and you’re in an area with good sunlight, relatively gentle weather (frequent hurricanes, tornadoes and wildfires are not recommended), and low pollution levels, an aquaponics system can work quite nicely. In fact, some homeowners have very simplistic setups in their backyards that don’t look very much different from ordinary raised beds. Keep in mind that almost any structure (a carport, an unused shed or garage, an abandoned (but structurally sound) building or warehouse) can be employed in place of a traditional greenhouse. They’ll offer most of the benefits, although they’ll usually require artificial lighting instead.
Greenhouses and other structures offer some specific advantages, including maintaining a more constant temperature, or even providing seasonal heating or cooling. The air contained within an enclosure keeps the humidity level manageable and reduces water lost through evaporation. When wind doesn’t carry seeds, dust and fungal spores through your crops and tanks, you can eliminate issues with weeds, diseases and most other pests. Birds, racoons and other wildlife are less likely to enter a greenhouse to feast on your strawberries (or even on your fish!), and your equipment is better protected within an enclosure like a greenhouse. Before you let this discourage you, though, keep in mind that a greenhouse can be as fancy as a custom glass enclosure in the modern Tudor style, or a simple series of half-hoops, covered with plastic, that can be erected over a weekend with a few helpful buddies. BTL Liners’ ArmorClear covers are an excellent choice in that case. (https://www.btlliners.com/armorclear) Even that old barn out back can be pressed into good use!