There is no science about the issue at hand. It is impossible to generate 40% waste nutes by fertigating to 20% runoff, whether it is done 1 time or 50 times a day. The arithmetic is simple. The percentage figure normally used is runoff divided by fertigation volume. Total runoff for the day divided by total input for the day will still be 20% at the end of the day - not science, just straight arithmetic. It appears that the calculations that I am familiar with are not being used. I would love to see numbers to clarify what the 40% actually means.