diff --git a/plate-tool-lib/src/csv/auto.rs b/plate-tool-lib/src/csv/auto.rs
index 3b2da65..e330b20 100644
--- a/plate-tool-lib/src/csv/auto.rs
+++ b/plate-tool-lib/src/csv/auto.rs
@@ -41,8 +41,8 @@ fn find_unique_plates(records: &[TransferRecord]) -> UniquePlates {
     let mut destination_names: HashSet<&str> = HashSet::new();
 
     for record in records {
-        source_names.insert(&record.source_well);
-        destination_names.insert(&record.destination_well);
+        source_names.insert(&record.source_plate);
+        destination_names.insert(&record.destination_plate);
     }
 
     let mut sources: Vec<PlateInstance> = Vec::with_capacity(source_names.len());
diff --git a/plate-tool-lib/src/plate_instances.rs b/plate-tool-lib/src/plate_instances.rs
index 649a797..3ee4c70 100644
--- a/plate-tool-lib/src/plate_instances.rs
+++ b/plate-tool-lib/src/plate_instances.rs
@@ -2,7 +2,7 @@ use super::plate::*;
 use serde::{Deserialize, Serialize};
 use uuid::Uuid;
 
-#[derive(PartialEq, Clone, Serialize, Deserialize)]
+#[derive(PartialEq, Clone, Serialize, Deserialize, Debug)]
 pub struct PlateInstance {
     pub plate: Plate,
     #[serde(rename = "id_v7")]