PH Range: 3.5-8 Ph (3.5-6.5 ACID, 7 NOR, 7-8 ALKALI). - PH Range: 3.5-8PH ( 3.5-7 Acid, 7-8 Alkaline). Step 5: Remove probe from soil and wipe clean after each use. Step 3: Adjust the position of the probe until the pointer on the dial swing slightly.
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