Index: dialin/ui/hd_simulator.py
===================================================================
diff -u -r26139e6df4a8c681817dcaec9775fce694a5037b -rb063060e7188711b0c50b7c700137e71870ccd99
--- dialin/ui/hd_simulator.py	(.../hd_simulator.py)	(revision 26139e6df4a8c681817dcaec9775fce694a5037b)
+++ dialin/ui/hd_simulator.py	(.../hd_simulator.py)	(revision b063060e7188711b0c50b7c700137e71870ccd99)
@@ -1836,8 +1836,8 @@
                                              actual_treatment_duration: int,
                                              acid_concentrate_type: int,
                                              bicarbonate_concentrate_type: int,
-                                             potassium_concentration: int,
-                                             calcium_concentration: int,
+                                             potassium_concentration: float,
+                                             calcium_concentration: float,
                                              bicarbonate_concentration: int,
                                              sodium_concentration: int,
                                              dialysate_temperature: float,
@@ -1914,8 +1914,8 @@
         payload += unsigned_integer_to_bytearray(int(actual_treatment_duration))
         payload += unsigned_integer_to_bytearray(int(acid_concentrate_type))
         payload += unsigned_integer_to_bytearray(int(bicarbonate_concentrate_type))
-        payload += unsigned_integer_to_bytearray(int(potassium_concentration))
-        payload += unsigned_integer_to_bytearray(int(calcium_concentration))
+        payload += float_to_bytearray(float(potassium_concentration))
+        payload += float_to_bytearray(float(calcium_concentration))
         payload += unsigned_integer_to_bytearray(int(bicarbonate_concentration))
         payload += unsigned_integer_to_bytearray(int(sodium_concentration))
         payload += float_to_bytearray(float(dialysate_temperature))