Anyone ever tank mixed msma first then certainty second in a big 200 gallon tank. I mixed my msma tonight and customer called and has a lot of johnson grass and msma wont kill it in one shot, I need the certainty also. Too much to use pump up sprayer. Also if you have is it a hot mix. Spraying on bermuda in 90 degree heat and rains tonight. Im going to read the label again to see if it has any info. on it. Just curious about any thoughts. I am also using liquid iron to counter the yellowing of msma.