The ebb and flow floor system has the added benefit
of costing less than a bench system. A floor system
may cost $2 to $3 per square foot compared with $5
to $6 per square foot for a bench system. There are
no aisles in a floor system so all the area can be used
for production. A good system requires a level floor,
so set screed boards for laying the concrete with a
laser level. After the 3-inch concrete floor has set,
1/4" wide by 1/2" deep grooves are cut on 2" centers
to allow the nutrient solution to drain back to the
storage tank.