diff --git a/workflows/sars-cov-2-variant-calling/sars-cov-2-ont-artic-variant-calling/ont-artic-variation.ga b/workflows/sars-cov-2-variant-calling/sars-cov-2-ont-artic-variant-calling/ont-artic-variation.ga
index f373025c63..0a5598e567 100644
--- a/workflows/sars-cov-2-variant-calling/sars-cov-2-ont-artic-variant-calling/ont-artic-variation.ga
+++ b/workflows/sars-cov-2-variant-calling/sars-cov-2-ont-artic-variant-calling/ont-artic-variation.ga
@@ -85,7 +85,7 @@
             "input_connections": {},
             "inputs": [
                 {
-                    "description": "Discard reads that are longer than this length",
+                    "description": "Discard reads that are longer than this length (recommended 1.75 * amplicon size to discard chimeras)",
                     "name": "Maximum read length"
                 }
             ],
@@ -103,7 +103,7 @@
                 "y": 710.5
             },
             "tool_id": null,
-            "tool_state": "{\"default\": 700, \"parameter_type\": \"integer\", \"optional\": true}",
+            "tool_state": "{\"default\": 700, \"parameter_type\": \"integer\", \"optional\": false}",
             "tool_version": null,
             "type": "parameter_input",
             "uuid": "be62c106-273a-4102-a9a1-1376525e4f4e",