diff --git a/frontend/src/pages/tagged_resources_page.tsx b/frontend/src/pages/tagged_resources_page.tsx
index af7b9ba..82d52c0 100644
--- a/frontend/src/pages/tagged_resources_page.tsx
+++ b/frontend/src/pages/tagged_resources_page.tsx
@@ -51,7 +51,7 @@ export default function TaggedResourcesPage() {
         }} />
       }
     </div>
-    {tag?.type && <h2 className={"text-base-content/60 ml-2 text-xl pl-2 mb-2"}>{tag.type}</h2>}
+    {tag?.type && <h2 className={"text-base-content/60 ml-2 text-lg pl-2 mb-2"}>{tag.type}</h2>}
     <div className={"px-3"}>
       {
         (tag?.aliases ?? []).map((e) => {
diff --git a/server/dao/tag.go b/server/dao/tag.go
index 9b23f67..3db0904 100644
--- a/server/dao/tag.go
+++ b/server/dao/tag.go
@@ -64,6 +64,13 @@ func GetTagByName(name string) (model.Tag, error) {
 }
 
 func SetTagInfo(id uint, description string, aliasOf *uint, tagType string) error {
+	old, err := GetTagByID(id)
+	if err != nil {
+		return err
+	}
+	if aliasOf != nil && len(old.Aliases) > 0 {
+		return model.NewRequestError("Tag already has aliases, cannot set alias_of")
+	}
 	t := model.Tag{Model: gorm.Model{
 		ID: id,
 	}, Description: description, Type: tagType, AliasOf: aliasOf}