diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/AbstractChartFragment.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/AbstractChartFragment.java
index 1c0ce68b..7be2afcb 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/AbstractChartFragment.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/activities/charts/AbstractChartFragment.java
@@ -272,9 +272,6 @@ public abstract class AbstractChartFragment extends AbstractGBFragment {
      * @param tsTo
      */
     protected List<ActivitySample> getAllSamples(DBHandler db, GBDevice device, int tsFrom, int tsTo) {
-        if (tsFrom == -1) {
-            tsFrom = getTSLast24Hours(tsTo);
-        }
         SampleProvider provider = getProvider(device);
         return db.getAllActivitySamples(tsFrom, tsTo, provider);
     }
@@ -284,18 +281,12 @@ public abstract class AbstractChartFragment extends AbstractGBFragment {
     }
 
     protected List<ActivitySample> getActivitySamples(DBHandler db, GBDevice device, int tsFrom, int tsTo) {
-        if (tsFrom == -1) {
-            tsFrom = getTSLast24Hours(tsTo);
-        }
         SampleProvider provider = getProvider(device);
         return db.getActivitySamples(tsFrom, tsTo, provider);
     }
 
 
     protected List<ActivitySample> getSleepSamples(DBHandler db, GBDevice device, int tsFrom, int tsTo) {
-        if (tsFrom == -1) {
-            tsFrom = getTSLast24Hours(tsTo);
-        }
         SampleProvider provider = getProvider(device);
         return db.getSleepSamples(tsFrom, tsTo, provider);
     }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/database/ActivityDatabaseHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/database/ActivityDatabaseHandler.java
index f80fee19..e2dfeef0 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/database/ActivityDatabaseHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/database/ActivityDatabaseHandler.java
@@ -162,8 +162,11 @@ public class ActivityDatabaseHandler extends SQLiteOpenHelper implements DBHandl
      * @return
      */
     private ArrayList<ActivitySample> getGBActivitySamples(int timestamp_from, int timestamp_to, int activityTypes, SampleProvider provider) {
-        if (timestamp_to == -1) {
-            timestamp_to = Integer.MAX_VALUE; // dont know what happens when I use more than max of a signed int
+        if (timestamp_to < 0) {
+            throw new IllegalArgumentException("negative timestamp_to");
+        }
+        if (timestamp_from < 0) {
+            throw new IllegalArgumentException("negative timestamp_from");
         }
         ArrayList<ActivitySample> samples = new ArrayList<ActivitySample>();
         final String where = "(provider=" + provider.getID() + " and timestamp>=" + timestamp_from + " and timestamp<=" + timestamp_to + getWhereClauseFor(activityTypes, provider) + ")";