where did you read that joebuck that is not correct., you want to test your water after you add nutes, the nutes will change your ph level!!! You dont stick anything into the soil you test the drainage that is why the strips or a meter are beter than the solution because the dirty drainage water will trow off the color of the solution. You want to test your water when you add nutes and your drainage of the soil and you should keep it around 6.5 - 6.8.. Good luck