I have 2 pH testers. They seem to give a little bit different readings, and now I have a couple of questions about pH. One meter has prongs approx. 4inces long... the other has prongs approx. 8 inches long. The Ferry Morse meter uses a 1.5V battery, the other uses no battery at all. In the first pic I have both meters buried about 4 inces deep. The reading on the Ferry is about 6.7 while the other one reads about 6.2 or so. I assume that this part is no big deal. This is where I have a question... In the second pick I have the meter with longer probes buried to about 8 inches. The meter reads about 5.2. Should the soil carry a more consistent reading, or is it possible to have different readings depending on the depth? If I show a lower pH at a deeper level, should I adjust the pH level at that level? If I do adjust it then it would also affect the soil towards the top of the pot also, right? Just a note.... If I dig down with my finger a couple of inches I can feel some small roots. I can also feel them deeper down when I push the longer probe in. Does the fact that I can feel roots a couple inches down mean anything (like maybe overwatering)?