diff --git a/freqtrade/optimize/hyperopt_auto.py b/freqtrade/optimize/hyperopt_auto.py
index c4d6f1581..f86204406 100644
--- a/freqtrade/optimize/hyperopt_auto.py
+++ b/freqtrade/optimize/hyperopt_auto.py
@@ -27,7 +27,7 @@ class HyperOptAuto(IHyperOpt):
             for attr_name, attr in self.strategy.enumerate_parameters('buy'):
                 if attr.optimize:
                     # noinspection PyProtectedMember
-                    attr._set_value(params[attr_name])
+                    attr.value = params[attr_name]
             return self.strategy.populate_buy_trend(dataframe, metadata)
 
         return populate_buy_trend
@@ -37,7 +37,7 @@ class HyperOptAuto(IHyperOpt):
             for attr_name, attr in self.strategy.enumerate_parameters('sell'):
                 if attr.optimize:
                     # noinspection PyProtectedMember
-                    attr._set_value(params[attr_name])
+                    attr.value = params[attr_name]
             return self.strategy.populate_sell_trend(dataframe, metadata)
 
         return populate_sell_trend
diff --git a/freqtrade/strategy/hyper.py b/freqtrade/strategy/hyper.py
index 35000d916..3fedda974 100644
--- a/freqtrade/strategy/hyper.py
+++ b/freqtrade/strategy/hyper.py
@@ -50,19 +50,11 @@ class BaseParameter(ABC):
         return f'{self.__class__.__name__}({self.value})'
 
     @abstractmethod
-    def get_space(self, name: str) -> Union['Integer', 'Real', 'Categorical']:
+    def get_space(self, name: str) -> Union['Integer', 'Real', 'SKDecimal', 'Categorical']:
         """
         Get-space - will be used by Hyperopt to get the hyperopt Space
         """
 
-    def _set_value(self, value: Any):
-        """
-        Update current value. Used by hyperopt functions for the purpose where optimization and
-         value spaces differ.
-        :param value: A numerical value.
-        """
-        self.value = value
-
 
 class NumericParameter(BaseParameter):
     """ Internal parameter used for Numeric purposes """