diff --git a/js/common/view/graph/LinearGraphNode.js b/js/common/view/graph/LinearGraphNode.js
index 7d866c5b..7b22ddb5 100644
--- a/js/common/view/graph/LinearGraphNode.js
+++ b/js/common/view/graph/LinearGraphNode.js
@@ -170,10 +170,21 @@ define( require => {
         tickLabels.push( tickLabel );
       }
 
-      // indicators & associated properties
-      const valueH2OProperty = new NumberProperty( 0 );
-      const valueH3OProperty = new NumberProperty( 0 );
-      const valueOHProperty = new NumberProperty( 0 );
+      // Properties
+      const valueH2OProperty = new NumberProperty( 0, {
+        tandem: options.tandem.createTandem( 'valueH2OProperty' ),
+        phetioReadOnly: true
+      } );
+      const valueH3OProperty = new NumberProperty( 0, {
+        tandem: options.tandem.createTandem( 'valueH3OProperty' ),
+        phetioReadOnly: true
+      } );
+      const valueOHProperty = new NumberProperty( 0, {
+        tandem: options.tandem.createTandem( 'valueOHProperty' ),
+        phetioReadOnly: true
+      } );
+
+      // indicators
       const indicatorH2ONode = GraphIndicatorNode.createH2OIndicator( valueH2OProperty, {
         x: scaleNode.right - options.majorTickLength,
         tandem: options.tandem.createTandem( 'indicatorH2ONode' )
diff --git a/js/common/view/graph/LogarithmicGraphNode.js b/js/common/view/graph/LogarithmicGraphNode.js
index 3d369a38..203219b2 100644
--- a/js/common/view/graph/LogarithmicGraphNode.js
+++ b/js/common/view/graph/LogarithmicGraphNode.js
@@ -151,10 +151,21 @@ define( require => {
         }
       }
 
-      // indicators & associated properties
-      const valueH2OProperty = new NumberProperty( 0 );
-      const valueH3OProperty = new NumberProperty( 0 );
-      const valueOHProperty = new NumberProperty( 0 );
+      // Properties
+      const valueH2OProperty = new NumberProperty( 0, {
+        tandem: options.tandem.createTandem( 'valueH2OProperty' ),
+        phetioReadOnly: true
+      } );
+      const valueH3OProperty = new NumberProperty( 0, {
+        tandem: options.tandem.createTandem( 'valueH3OProperty' ),
+        phetioReadOnly: true
+      } );
+      const valueOHProperty = new NumberProperty( 0, {
+        tandem: options.tandem.createTandem( 'valueOHProperty' ),
+        phetioReadOnly: true
+      } );
+
+      // indicators
       const indicatorH2ONode = GraphIndicatorNode.createH2OIndicator( valueH2OProperty, {
         x: backgroundNode.right - options.indicatorXOffset,
         tandem: options.tandem.createTandem( 'indicatorH2ONode' )
diff --git a/js/phet-io/ph-scale-phet-io-elements-baseline.js b/js/phet-io/ph-scale-phet-io-elements-baseline.js
index e562ff76..8bd8f7c8 100644
--- a/js/phet-io/ph-scale-phet-io-elements-baseline.js
+++ b/js/phet-io/ph-scale-phet-io-elements-baseline.js
@@ -7775,6 +7775,45 @@ window.phet.phetio.phetioElementsBaseline = assert &&
       "phetioStudioControl": true,
       "phetioTypeName": "PropertyIO<NullableIO<BooleanIO>>"
     },
+    "phScale.microScreen.view.graphNode.linearGraphNode.valueH2OProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
+    "phScale.microScreen.view.graphNode.linearGraphNode.valueH3OProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
+    "phScale.microScreen.view.graphNode.linearGraphNode.valueOHProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
     "phScale.microScreen.view.graphNode.linearGraphNode.visibleProperty": {
       "phetioDocumentation": "Controls whether the Node will be visible (and interactive), see the NodeIO documentation for more details.",
       "phetioDynamicElement": false,
@@ -8243,6 +8282,45 @@ window.phet.phetio.phetioElementsBaseline = assert &&
       "phetioStudioControl": true,
       "phetioTypeName": "PropertyIO<NullableIO<BooleanIO>>"
     },
+    "phScale.microScreen.view.graphNode.logarithmicGraphNode.valueH2OProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
+    "phScale.microScreen.view.graphNode.logarithmicGraphNode.valueH3OProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
+    "phScale.microScreen.view.graphNode.logarithmicGraphNode.valueOHProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
     "phScale.microScreen.view.graphNode.logarithmicGraphNode.visibleProperty": {
       "phetioDocumentation": "Controls whether the Node will be visible (and interactive), see the NodeIO documentation for more details.",
       "phetioDynamicElement": false,
@@ -11363,6 +11441,45 @@ window.phet.phetio.phetioElementsBaseline = assert &&
       "phetioStudioControl": true,
       "phetioTypeName": "PropertyIO<NullableIO<BooleanIO>>"
     },
+    "phScale.mySolutionsScreen.view.graphNode.logarithmicGraphNode.valueH2OProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
+    "phScale.mySolutionsScreen.view.graphNode.logarithmicGraphNode.valueH3OProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
+    "phScale.mySolutionsScreen.view.graphNode.logarithmicGraphNode.valueOHProperty": {
+      "phetioDocumentation": "",
+      "phetioDynamicElement": false,
+      "phetioEventType": "MODEL",
+      "phetioFeatured": false,
+      "phetioHighFrequency": false,
+      "phetioIsArchetype": false,
+      "phetioPlayback": false,
+      "phetioReadOnly": true,
+      "phetioState": true,
+      "phetioStudioControl": true,
+      "phetioTypeName": "NumberPropertyIO"
+    },
     "phScale.mySolutionsScreen.view.graphNode.logarithmicGraphNode.visibleProperty": {
       "phetioDocumentation": "Controls whether the Node will be visible (and interactive), see the NodeIO documentation for more details.",
       "phetioDynamicElement": false,