No not the run off. If you are growing in soil the SOIL pH should be between 6 and 7 with optimal soil pH about 6.5. Need to let it swing about a bit because did chemicals are absorbed at dif pH. If you click on my name and look at my grow journal auto ultimate with Dutch pro nutes (in Dutch passion section,) I was having same questions last week. Ph5.8 for soil is wrong. Aim for a soil pH of 6.5.