Here’s a look at the aquaponics system water usage per month for the last 11 months. The monthly data is after the page break. The 4000 gallon system usage averages about 540 gallons per month producing around 250-300 heads of lettuce each month. That’s 18 gallons per day and takes roughly 2 gallons per head of lettuce on average. Pretty efficient system. I’m excited to get our mineralization tank installed to keep even more water in the system. Currently, everytime I flush the filter, the water is lost to the ground outside. Keeping it in a mineralization tank to extract even more nutrients and save water will add to the nutrient density of the produce and the water efficiency of the overall system.

Perusing the internet, the typical average to produce a one pound head of field grown lettuce is between 16 and 23 gallons of water. Our lettuce heads are a little less than a pound averaging close to 400 grams. So if we produce 300 heads at 400g each that is the equivalent of 264 heads of field grown lettuce at 454g each. Aquaponics lettuce at 2 gal per head equals 600 gallons to produce and at 16 gallons per head of field grown lettuce, it takes 4,224 gallons to produce. Pretty big difference.

Can we replace all field grown lettuce with Aquaponics? I don’t know that we could do that. There is a lot more infrastructure required to grow aquaponic lettuce. You need a greenhouse in most cases and heat in the cooler climates. However, in places where water and/or arable land is scarce, aquaponics is a solution worth considering. One grower in Hawaii, Zac Hosler of Living Aquaponics is converting lava fields over to aquaponics. How great is that? Farming land that you couldn’t even drill a seed into and producing. As droughts become more common in particular areas, aquaponics serves a great alternative to conventional farming affording the ability to grow nutritional produce with very little water.