Revising my figures to 5mph. 5 times 88 feet per minute is 440 feet. Times 7 feet wide equals 3080 sqft per minute. At .25 gal per thousand sqft that would be .77 gal per minute. (98.6 ounces) for solution output at the nozzle. Use a measuring jug and confirm this. If you spray at center to center 7 feet wide, and the machine is 3 feet wide, your wheel to wheel tracks are only 4 feet apart. And naturally you need to spray only 2 feet beyond the machine on each side, (and a bit more to provide overlap.) Can you show us a photo of the spray pattern of water on concrete? What width does your tape measure show? Your fertilizer would be thrown too far, too much overlap, it seems to me. Click my name and refer to the pattern on concrete from my Permagreen Ultra in my photographs. Ultra was sold 2 years ago. Photo set "PG Ultra and sprayer." The magnetic signs "Just say no to crabgrass" are still for sale.