diff --git a/server/fishtest/api.py b/server/fishtest/api.py
index 7179158d2..f06a95061 100644
--- a/server/fishtest/api.py
+++ b/server/fishtest/api.py
@@ -436,7 +436,7 @@ def get_task(self):
             task["last_updated"] = str(task["last_updated"])
         if "residual" in task:
             # json does not know about infinity
-            if task["residual"] == float("inf"):
+            if task.get("residual", None) == float("inf"):
                 task["residual"] = "inf"
         return task
 
diff --git a/server/fishtest/rundb.py b/server/fishtest/rundb.py
index fda483bb2..c723a9e9b 100644
--- a/server/fishtest/rundb.py
+++ b/server/fishtest/rundb.py
@@ -46,7 +46,7 @@
     get_hash,
     get_tc_ratio,
     remaining_hours,
-    update_residuals,
+    residual_to_color,
     worker_name,
 )
 from fishtest.workerdb import WorkerDb
@@ -554,7 +554,8 @@ def new_run(
             "tasks": [],
             "approved": False,
             "approver": "",
-            # Aggregated data
+            "bad_tasks": [],
+            # Aggregated results
             "results": {
                 "wins": 0,
                 "losses": 0,
@@ -1630,7 +1631,11 @@ def purge_run(self, run, p=0.001, res=7.0, iters=1):
         if run.get("failed", False):
             return "You cannot purge a failed run"
         message = "No bad workers"
-        # Transfer bad tasks to run["bad_tasks"]
+
+        # The following is necessary to be able to purge
+        # old runs. It can be deleted after 30 days
+        # (cfr above).
+
         if "bad_tasks" not in run:
             run["bad_tasks"] = []
 
@@ -1642,14 +1647,10 @@ def purge_run(self, run, p=0.001, res=7.0, iters=1):
             # Special cases: crashes or time losses.
             if crash_or_time(task):
                 message = ""
-                # The residual or residual color my not have been set yet
-                self.set_bad_task(task_id, run, residual=10.0, residual_color="#FF6A6A")
+                # The residual or residual color may not have been set yet
+                self.set_bad_task(task_id, run, residual=10.0, residual_color="red")
 
         chi2 = get_chi2(run["tasks"])
-        # Make sure the residuals are up to date.
-        # Once a task is moved to run["bad_tasks"] its
-        # residual will no longer change.
-        update_residuals(run["tasks"], cached_chi2=chi2)
         bad_workers = get_bad_workers(
             run["tasks"],
             cached_chi2=chi2,
@@ -1663,7 +1664,13 @@ def purge_run(self, run, p=0.001, res=7.0, iters=1):
                 continue
             if task["worker_info"]["unique_key"] in bad_workers:
                 message = ""
-                self.set_bad_task(task_id, run)
+                residual = chi2["residual"].get(
+                    task["worker_info"]["unique_key"], float("inf")
+                )
+                residual_color = residual_to_color(residual, chi2)
+                self.set_bad_task(
+                    task_id, run, residual=residual, residual_color=residual_color
+                )
 
         if message == "":
             results = compute_results(run)
diff --git a/server/fishtest/schemas.py b/server/fishtest/schemas.py
index c9b18bd9a..ddc7b9dcc 100644
--- a/server/fishtest/schemas.py
+++ b/server/fishtest/schemas.py
@@ -62,6 +62,7 @@
 even = div(2, name="even")
 datetime_utc = intersect(datetime, fields({"tzinfo": timezone.utc}))
 gzip_data = magic("application/gzip", name="gzip_data")
+residual_color = set_name(union("green", "yellow", "red"), "residual_color")
 
 uint = intersect(int, ge(0))
 suint = intersect(int, gt(0))
@@ -640,7 +641,7 @@ def flags_must_match(run):
 # about non-validation of runs created with the prior
 # schema.
 
-RUN_VERSION = 6
+RUN_VERSION = 7
 
 runs_schema = intersect(
     {
@@ -762,8 +763,6 @@ def flags_must_match(run):
                     "active": bool,
                     "last_updated": datetime_utc,
                     "start": uint,
-                    "residual?": number,
-                    "residual_color?": str,
                     "bad?": True,
                     "stats": results_schema,
                     "worker_info": worker_info_schema_runs,
@@ -772,14 +771,14 @@ def flags_must_match(run):
             ),
             ...,
         ],
-        "bad_tasks?": [
+        "bad_tasks": [
             {
                 "num_games": intersect(uint, even),
                 "active": False,
                 "last_updated": datetime_utc,
                 "start": uint,
                 "residual": number,
-                "residual_color": str,
+                "residual_color": residual_color,
                 "bad": True,
                 "task_id": task_id,
                 "stats": results_schema,
diff --git a/server/fishtest/templates/tasks.mak b/server/fishtest/templates/tasks.mak
index 62b71d04b..5302bff4f 100644
--- a/server/fishtest/templates/tasks.mak
+++ b/server/fishtest/templates/tasks.mak
@@ -1,5 +1,5 @@
 <%!
-  from fishtest.util import worker_name
+  from fishtest.util import worker_name, display_residual
 %>
 
 % for idx, task in enumerate(run['tasks'] + run.get('bad_tasks', [])):
@@ -70,9 +70,12 @@
     <td>${stats.get('time_losses', '-')}</td>
 
     % if 'spsa' not in run['args']:
-      % if 'residual' in task and task['residual']!=float("inf"):
-        <td style="background-color:${task['residual_color']}">
-          ${f"{task['residual']:.3f}"}
+      <%
+        d=display_residual(task, chi2)
+      %>
+      % if d['residual']!=float("inf"):
+        <td style="background-color:${d['display_color']}">
+          ${f"{d['residual']:.3f}"}
         </td>
       % else:
         <td>-</td>
diff --git a/server/fishtest/util.py b/server/fishtest/util.py
index 37da5d9e0..eea12a311 100644
--- a/server/fishtest/util.py
+++ b/server/fishtest/util.py
@@ -209,30 +209,44 @@ def get_bad_workers(tasks, cached_chi2=None, p=0.001, res=7.0, iters=1):
     return bad_workers
 
 
-def update_residuals(tasks, cached_chi2=None):
-    # If we have an up-to-date result of get_chi2() we can pass
-    # it as cached_chi2 to avoid needless recomputation.
-    chi2 = get_chi2(tasks) if cached_chi2 is None else cached_chi2
-    residuals = chi2["residual"]
+def residual_to_color(residual, chi2):
+    if abs(residual) < chi2["z_95"]:
+        return "green"
+    elif abs(residual) < chi2["z_99"]:
+        return "yellow"
+    else:
+        return "red"
 
-    for task in tasks:
-        if "bad" in task:
-            continue
-        if "worker_info" not in task:
-            continue
-        task["residual"] = residuals.get(
-            task["worker_info"]["unique_key"], float("inf")
-        )
 
+def display_residual(task, chi2):
+    if "bad" in task and "residual" in task:
+        residual = task["residual"]
+        residual_color = task["residual_color"]
+    else:
         if crash_or_time(task):
-            task["residual"] = 10.0
-            task["residual_color"] = "#FF6A6A"
-        elif abs(task["residual"]) < chi2["z_95"]:
-            task["residual_color"] = "#44EB44"
-        elif abs(task["residual"]) < chi2["z_99"]:
-            task["residual_color"] = "yellow"
+            residual = 10.0
+            residual_color = "red"
         else:
-            task["residual_color"] = "#FF6A6A"
+            residual = chi2["residual"].get(
+                task["worker_info"]["unique_key"], float("inf")
+            )
+            residual_color = residual_to_color(residual, chi2)
+
+    display_colors = {
+        "green": "#44EB44",
+        "yellow": "yellow",
+        "red": "#FF6A6A",
+        "#44EB44": "#44EB44",  # legacy bad tasks
+        "#FF6A6A": "#FF6A6A",
+    }
+
+    display_color = display_colors[residual_color]
+
+    return {
+        "residual": residual,
+        "residual_color": residual_color,
+        "display_color": display_color,
+    }
 
 
 def format_bounds(elo_model, elo0, elo1):
diff --git a/server/fishtest/views.py b/server/fishtest/views.py
index e560520c2..21f0c54dd 100644
--- a/server/fishtest/views.py
+++ b/server/fishtest/views.py
@@ -23,7 +23,6 @@
     github_repo_valid,
     is_sprt_ltc_data,
     password_strength,
-    update_residuals,
 )
 from pyramid.httpexceptions import HTTPFound, HTTPNotFound
 from pyramid.security import forget, remember
@@ -1461,6 +1460,7 @@ def tests_tasks(request):
     run = request.rundb.get_run(request.matchdict["id"])
     if run is None:
         raise HTTPNotFound()
+    chi2 = get_chi2(run["tasks"])
 
     try:
         show_task = int(request.params.get("show_task", -1))
@@ -1473,6 +1473,7 @@ def tests_tasks(request):
         "run": run,
         "approver": request.has_permission("approve_run"),
         "show_task": show_task,
+        "chi2": chi2,
     }
 
 
@@ -1603,7 +1604,6 @@ def tests_view(request):
             cores += task["worker_info"]["concurrency"]
 
     chi2 = get_chi2(run["tasks"])
-    update_residuals(run["tasks"], cached_chi2=chi2)
 
     try:
         show_task = int(request.params.get("show_task", -1))