diff --git a/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/heatmaps/WellTooltipGenerator.java b/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/heatmaps/WellTooltipGenerator.java
index 55b83c83fb6a7d21441c03e414d2bbaef90f1dd7..3860ef76e6e4241be4fd6695fe20de0190a5fed2 100644
--- a/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/heatmaps/WellTooltipGenerator.java
+++ b/screening/source/java/ch/systemsx/cisd/openbis/plugin/screening/client/web/client/application/detailviewers/heatmaps/WellTooltipGenerator.java
@@ -38,7 +38,7 @@ class WellTooltipGenerator implements HeatmapPresenter.IWellTooltipGenerator
 {
     private static final String NEWLINE = "\n";
 
-    private static final int MAX_DESCRIBED_FEATURES = 30;
+    private static final int MAX_DESCRIBED_FEATURES = 20;
 
     private final PlateLayouterModel model;