diff --git a/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java b/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java
index 42f11a8..1917476 100644
--- a/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java
+++ b/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java
@@ -38,16 +38,6 @@ public abstract class ParamField extends JPanel {
 	protected static RequestView requestView;
 	protected String paramName;
 
-	// TODO: Add tooltip text based on rr.table_column.column_description
-	public ParamField(RequestView requestView, String paramName, String strLabel) {
-		super();
-		this.setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
-		JLabel label = new JLabel(strLabel + " ");
-		this.add(label);
-		this.requestView = requestView;
-		this.paramName = paramName;
-	}
-
 	public ParamField(RequestView requestView, String paramName) {
 		super();
 		this.setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
@@ -55,6 +45,7 @@ public abstract class ParamField extends JPanel {
 		JLabel label = new JLabel(strLabel.substring(0, 1).toUpperCase() + strLabel.substring(1));
 		label.setPreferredSize(new Dimension(140, 15));
 		this.add(label);
+		// TODO: Add tooltip text based on rr.table_column.column_description
 		this.requestView = requestView;
 		this.paramName = paramName;
 	}
@@ -77,13 +68,6 @@ public abstract class ParamField extends JPanel {
 	}
 
 	public static class FloatField extends ParamField {
-		FloatField(RequestView requestView, String paramName, String strLabel) {
-			super(requestView, paramName, strLabel);
-			JTextField field = new JTextField();
-			addChangeListener(field, e -> onUpdate(field));
-			this.add(field);
-		}
-
 		FloatField(RequestView requestView, String paramName) {
 			super(requestView, paramName);
 			JTextField field = new JTextField();
@@ -140,17 +124,33 @@ public abstract class ParamField extends JPanel {
 	}
 
 	public static class FloatRangeField extends ParamField {
-		FloatField fieldMin;
-		FloatField fieldMax;
+		JTextField fieldMin;
+		JTextField fieldMax;
 
 		FloatRangeField(RequestView requestView, String paramName) {
 			super(requestView, paramName);
-			fieldMin = new FloatField(requestView, paramName + MIN_SUFFIX, "min");
+			fieldMin = new JTextField();
+			addChangeListener(fieldMin, e -> onUpdate(fieldMin, MIN_SUFFIX));
 			this.add(fieldMin);
 
-			fieldMax = new FloatField(requestView, paramName + MAX_SUFFIX, "max");
+			fieldMax = new JTextField();
+			addChangeListener(fieldMax, e -> onUpdate(fieldMax, MAX_SUFFIX));
 			this.add(fieldMax);
 		}
+
+		private void onUpdate(JTextField field, String suffix) {
+			if ("".equals(field.getText())) {
+				field.setBackground(Color.WHITE);
+				requestView.updateParam(paramName + suffix, null);
+			} else {
+				try {
+					requestView.updateParam(paramName + suffix, Float.parseFloat(field.getText()));
+					field.setBackground(Color.WHITE);
+				} catch (NumberFormatException e) {
+					field.setBackground(Color.PINK);
+				}
+			}
+		}
 	}
 
 	public static class TargetNameField extends ParamField {
--
libgit2 0.21.2