Update app.py

app.py

@@ -726,10 +726,11 @@ class HydroCalculator:
         for name, grams in self.fertilizers:
             for element, ratio in fertilizers_db[name].items():
                 ppm[element] = ppm.get(element, 0) + (grams * ratio * 1000) / (self.volume * 10)
+                ppm_ec[element] = ppm.get(element, 0) + (grams * ratio * 1000) / (self.volume * 10)
         return ppm
 
     def calculate_ec(self):
-        ppm = self.calculate_ppm()
+        ppm_ec = self.calculate_ppm()
         ec = 0.0
         EC_COEFFICIENTS = {
             'N (NO3-)': 0.6,