PH

1stly. You can PH water that runs off from soil U need a soil ph meter. This method can only be applied with coco.. As with soil nutrients are taken in different and oh its just too long to explain. U just can't ph like that. The ph solution you're putting in works as you say. So, if there was issues, you'd of seen them by now And BTW, you shouldn't be wetting the soil enough to get run off. Good luck.

Hi buddy so I take it the first reading is the plant medium itself and the 2nd reading is the run off at 7.2 ? with run off it should only really be 0.5 over what your soil is at. the only way I can see this changing buddy is to use less of a potent mx of nutrients or just ease up on them keep and eye on her for a few days keep testing run off until your back down to normal levels one of the hradest things to get out of soil is nutrients thats why alot of growers prefer coco as its much easier to flush the medium and get rid of nutrients or top them up :) best of luck buddy

The soil, if pre-bought may have come with dolomite lime in it. That will always put your soil at a neutral pH value or close to it. If they look healthy, then don't stress. Continue to water at 6.1 pH and eventually it will come down. But if there's significant dolomite lime in it then it might take awhile until the lime has broken down. That could take awhile depending on how much lime was added.