Check your potassium source. Should not be derived from muriate of potash. Too much chlorine there. Your grass will not tolerate it and die slowly. Your best would be potassium nitrate. Potassium sulfate is available in many of the Lesco products which is not quite so bad. It's hard to find at some stores. 14-2-14 Lesco number 098323. At least check the analysis for chlorine percentage before doing anything further. potassium nitrate is available in liquid soluble form and is product of choice for centipede. Write is need further info.
We all are merely gleaners from the masters who were here before us.