My system is a pressure fed system.It has 1 1/4 pipes.Field appears to be o.k. only 1 spot where grass is green.I found the ends of the 4 laterals this weekend.I'm guessing that some of the holes are plugged in the pipes.Can see some black sludge in the last hole of every pipe and system is 17yrs old.I'm going to add flush valves to the ends and clean them out.Can your product be added the the field even if it is not saturated yet?