diff --git a/library/grow/moisture.py b/library/grow/moisture.py
index d421967..c751940 100644
--- a/library/grow/moisture.py
+++ b/library/grow/moisture.py
@@ -3,91 +3,55 @@ import atexit
 import RPi.GPIO as GPIO
 
 MOISTURE_1_PIN = 23
-MOISTURE_2_PIN = 25
-MOISTURE_3_PIN = 8
-
-_is_setup = False
+MOISTURE_2_PIN = 8
+MOISTURE_3_PIN = 25
+MOISTURE_INT_PIN = 4
 
 
 class Moisture(object):
-    __slots__ = 'in1', 'in2', 'in3'
+    def __init__(self, channel=0):
+        self._gpio_pin = [MOISTURE_1_PIN, MOISTURE_2_PIN, MOISTURE_3_PIN, MOISTURE_INT_PIN][channel]
 
-    def __init__(self, in1, in2, in3):
-        self.in1 = in1
-        self.in2 = in2
-        self.in3 = in3
+        GPIO.setwarnings(False)
+        GPIO.setmode(GPIO.BCM)
+        GPIO.setup(self._gpio_pin, GPIO.IN)
 
-    def __repr__(self):
-        fmt = """Moisture 1: {in1} Hz
-Moisture 1: {in2} Ohms
-Moisture 1: {in3} Ohms"""
-        
-        return fmt.format(
-            in1=self.in1,
-            in2=self.in2,
-            in3=self.in3)
+        self._count = 0
+        self._reading = 0
+        self._wet_point = 0
+        self._dry_point = 0
+        self._time_start = time.time()
+        GPIO.add_event_detect(self._gpio_pin, GPIO.RISING, callback=self._event_handler, bouncetime=1)
 
-    __str__ = __repr__
+    def set_wet_point(self, value=None):
+        self._wet_point = value if value is not None else self.raw_moisture
 
+    def set_dry_point(self, value=None):
+        self._dry_point = value if value is not None else self.raw_moisture
 
-def setup():
-    global _is_setup
-    global _moisture
-    
-    if _is_setup:
-        return
-    _is_setup = True
+    def _event_handler(self, pin):
+        self._count += 1
+        if self.time_elapsed >= 1.0:
+            self._reading = self._count / self.time_elapsed
+            self._count = 0
+            self._time_start = time.time()
 
-    GPIO.setwarnings(False)
-    GPIO.setmode(GPIO.BCM)
-    GPIO.setup(MOISTURE_1_PIN, GPIO.IN)
-    GPIO.input(MOISTURE_1_PIN)
-    GPIO.setup(MOISTURE_2_PIN, GPIO.IN)
-    GPIO.input(MOISTURE_2_PIN)
-    GPIO.setup(MOISTURE_3_PIN, GPIO.IN)
-    GPIO.input(MOISTURE_3_PIN)
-    
-    atexit.register(cleanup)
+    @property
+    def time_elapsed(self):
+        return time.time() - self._time_start
 
+    @property
+    def raw_moisture(self):
+        return self._reading
 
-def set_moisture_wet(channel, value):
-    """Set wet point for a moisture channel."""
-    _moisture[channel].wet = value
+    @property
+    def moisture(self):
+        return self.raw_moisture
 
-def set_moisture_wet(channel, value):
-    """Set wet point for a moisture channel."""
-    _moisture[channel].dry = value
+    @property
+    def range(self):
+        return self._wet_point - self._dry_point
 
-def read_moiture(channel):
-    """Get current value for the additional ADC pin."""
-    setup()
-    return _moisture[channel].value
-
-def cleanup():
-    GPIO.output(MOISTURE_1_PIN, 0)
-    GPIO.output(MOISTURE_2_PIN, 0)
-    GPIO.output(MOISTURE_3_PIN, 0)
-
-def read_all():
-    """Return gas resistence for oxidising, reducing and NH3"""
-    setup()
-    in1 = adc.get_voltage('in0/gnd')
-    in2 = adc.get_voltage('in1/gnd')
-    in3 = adc.get_voltage('in2/gnd')
-
-    try:
-        in1 = (ox * 56000) / (3.3 - ox)
-    except ZeroDivisionError:
-        in1 = 0
-
-    try:
-        in2 = (red * 56000) / (3.3 - red)
-    except ZeroDivisionError:
-        in2 = 0
-
-    try:
-        in3 = (nh3 * 56000) / (3.3 - nh3)
-    except ZeroDivisionError:
-        in3 = 0
-
-    return _moisture(in1, in2, in3)
+    @property
+    def saturation(self):
+        return float(self.moisture - self._dry_point) / self.range