I like my current soil and I feel my plants grow pretty good in it. It is called Sea Soil Original. It is OMRI and packed with macro and micro nutrients. My plants have been growing very well in them. My plants at about a month filled their 1.5 gallon pots. I was underfeeding and all 4 got a nitrogen deficiency. I transplanted into 5 gallon buckets and watered with 1.5 gallons of water with full strength nutes. On the first plant I watered with 7.5 water, runoff was 5.6. On the second plant I used 8.0 water, runoff was 5.7. On the third plant I used 8.5 and runoff was 5.7. I use 2 different and frequently calibrated PH meters to check my PH. I stuck my PH meter into the top soil, that was damp, and it said 6.4. My runoffs are wierd, if its the same soil it seem impossible to get the same runoff with different PH'd water? Also when I stick my meters into all the soils that are still wet I get 6.2 - 6.5 readings, does this mean thats the PH for my plants? I know phosphorous and maybe nitrogen are locked out in lower 5.0 - 5.9 range and my plants need the nutrients. What should I do? note - The day after transplant and water leaves have perked up. Old growth that was brown/yellow remains the same but new growth is perked up and looking really healthy. If anyone thinks pics would help just ask.
In a 7.0 solution they both test 7.0 and 4.1 in the 4.1 solution. It is a milwaukee p600 and Oak-something eco tester. My plants actually seem to be doing fairly good, the new growth is looking really healthy.
Sounds like you have some heavily nuted soil. From my limited observation organics tend to tank the ph. I would top dress with lime and flush with 7.0 or 7.5 until the runoff comes up. May cost you some of the nutes in the soil, but I think you would see your ph stabilize at a more normal level. Runoff ph should also rise some as the plants consume nutes as well. I dont know about the other meter, but that ph600 is made for liquid and isnt going to give an accurate reading sticking it in the dirt.
OK, I would not trust any pH readings with the electrodes in soil, not meant to work that way. They have to be immersed in liquid.