diff --git a/ckanext/charts/chart_builders/plotly.py b/ckanext/charts/chart_builders/plotly.py
index 4dafb0b..8ad1ace 100644
--- a/ckanext/charts/chart_builders/plotly.py
+++ b/ckanext/charts/chart_builders/plotly.py
@@ -28,16 +28,45 @@ def get_supported_forms(cls) -> list[type[Any]]:
 
 class PlotlyBarBuilder(PlotlyBuilder):
     def to_json(self) -> str:
-        return cast(str, px.bar(self.df, **self.settings).to_json())
+        return self.build_bar_chart()
 
+    def build_bar_chart(self) -> Any:
+        if self.settings.get("skip_null_values"):
+            self.df = self.df[self.df[self.settings["y"]].notna()]
+
+        fig = px.bar(
+            data_frame = self.df,
+            x = self.settings["x"],
+            y = self.settings["y"],
+        )
+
+        fig.update_xaxes(
+            type="category",
+        )
+
+        return fig.to_json()
 
-class PlotlyHorizontalBarBuilder(PlotlyBuilder):
-    def __init__(self, df: pd.DataFrame, settings: dict[str, Any]) -> None:
-        super().__init__(df, settings)
-        self.settings["orientation"] = "h"
 
+class PlotlyHorizontalBarBuilder(PlotlyBuilder):
     def to_json(self) -> Any:
-        return px.bar(self.df, **self.settings).to_json()
+        return self.build_horizontal_bar_chart()
+
+    def build_horizontal_bar_chart(self) -> Any:
+        if self.settings.get("skip_null_values"):
+            self.df = self.df[self.df[self.settings["y"]].notna()]
+
+        fig = px.bar(
+            data_frame = self.df,
+            y = self.settings["x"],
+            x = self.settings["y"],
+            orientation="h",
+        )
+
+        fig.update_yaxes(
+            type="category",
+        )
+
+        return fig.to_json()
 
 
 class PlotlyPieBuilder(PlotlyBuilder):
@@ -208,10 +237,34 @@ def build_line_chart(self) -> Any:
 
 class PlotlyScatterBuilder(PlotlyBuilder):
     def to_json(self) -> Any:
-        try:
-            return px.scatter(self.df, **self.settings).to_json()
-        except Exception as e:
-            raise exception.ChartBuildError(f"Error building the chart: {e}")
+        return self.build_scatter_chart()
+
+
+    def build_scatter_chart(self) -> Any:
+        self.df = self.df.fillna(0)
+
+        if self.settings.get("skip_null_values"):
+            self.df = self.df.loc[self.df[self.settings["y"]] != 0]
+
+        if self.df[self.settings["size"]].dtype not in ["int64", "float64"]:
+            raise exception.ChartBuildError(
+                """The 'size' source should be a field of positive integer 
+                or float type."""
+            )
+
+        fig = px.scatter(
+            data_frame = self.df,
+            x = self.settings["x"],
+            y = self.settings["y"],
+            size = self.settings["size"],
+            size_max = self.settings["size_max"],
+        )
+
+        fig.update_xaxes(
+            type="category",
+        )
+
+        return fig.to_json()
 
 
 class BasePlotlyForm(BaseChartForm):
@@ -243,6 +296,7 @@ def get_form_fields(self):
             self.log_y_field(),
             self.sort_x_field(),
             self.sort_y_field(),
+            self.skip_null_values_field(),
             self.color_field(columns),
             self.animation_frame_field(columns),
             self.opacity_field(),
@@ -372,6 +426,7 @@ def get_form_fields(self):
             self.log_y_field(),
             self.sort_x_field(),
             self.sort_y_field(),
+            self.skip_null_values_field(),
             self.size_field(columns),
             self.size_max_field(),
             self.limit_field(),