diff --git a/reactor.html b/reactor.html
index 1b122db..77262ad 100644
--- a/reactor.html
+++ b/reactor.html
@@ -153,13 +153,18 @@
         <label for="node-input-length"><i class="fa fa-tag"></i> Reactor length [m]</label>
         <input type="text" id="node-input-length" placeholder="m">
     </div>
+    <h2> Simulation parameters </h2>
+    <div class="form-row">
+        <label for="node-input-timeStep"><i class="fa fa-tag"></i> Time step [s]</label>
+        <input type="text" id="node-input-timeStep" placeholder="s">
+    </div>
     <div class="form-row PFR">
-        <label for="node-input-resolution_L"><i class="fa fa-tag"></i> Resolution</label>
+        <label for="node-input-resolution_L"><i class="fa fa-tag"></i> Spatial resolution</label>
         <input type="text" id="node-input-resolution_L" placeholder="#">
     </div>
     <div class="form-row PFR">
-        <label for="node-input-dx"><i class="fa fa-tag"></i> dx (length / resolution) [m]</label>
-        <span id="dx-output" style="display: inline-block; padding: 8px; font-weight: bold; color: #333;">--</span>
+        <label for="node-input-dx"><i class="fa fa-tag"></i> Δx (length / resolution) [m]</label>
+        <span id="dx-output" style="display: inline-block; padding: 8px; font-weight: bold;">--</span>
     </div>
     <h3> Internal mass transfer calculation (optional) </h3>
     <div class="form-row">
@@ -220,11 +225,6 @@
         <label for="node-input-X_TS_init"><i class="fa fa-tag"></i> Initial total suspended solids [g TSS m-3]</label>
         <input type="text" id="node-input-X_TS_init" class="concentrations">
     </div>
-    <h2> Simulation parameters </h2>
-    <div class="form-row">
-        <label for="node-input-timeStep"><i class="fa fa-tag"></i> Time step [s]</label>
-        <input type="text" id="node-input-timeStep" placeholder="s">
-    </div>
 
     <!-- Logger fields injected here -->
 	<div id="logger-fields-placeholder"></div>