diff --git a/app.py b/app.py
index 880ae75..98c6a2e 100644
--- a/app.py
+++ b/app.py
@@ -3344,12 +3344,11 @@ def api_delete_iso(node, volid):
         return jsonify({"error": "Node not found"}), 404
 
     try:
-        # volid format: storage/filename.iso
-        parts = volid.split("/")
-        if len(parts) != 2:
+        # volid format: storage:content-type/filename.iso (e.g. local:iso/foo.iso)
+        if ":" not in volid or "/" not in volid:
             return jsonify({"error": "Invalid volume ID format"}), 400
 
-        storage = parts[0]
+        storage = volid.split(":")[0]
         proxmox.nodes(node).storage(storage).content(volid).delete()
 
         return jsonify(
@@ -3395,12 +3394,12 @@ def api_delete_lxc_template(node, volid):
         return jsonify({"error": "Node not found"}), 404
 
     try:
-        # volid format: storage/template-name.tar.xz
-        parts = volid.split("/")
-        if len(parts) != 2:
+        # volid format: storage:content-type/template-name.tar.xz
+        # (e.g. local:vztmpl/debian-12.tar.zst)
+        if ":" not in volid or "/" not in volid:
             return jsonify({"error": "Invalid volume ID format"}), 400
 
-        storage = parts[0]
+        storage = volid.split(":")[0]
         proxmox.nodes(node).storage(storage).content(volid).delete()
 
         return jsonify(
diff --git a/static/js/isos.js b/static/js/isos.js
index 9a5465a..83128cf 100644
--- a/static/js/isos.js
+++ b/static/js/isos.js
@@ -157,7 +157,7 @@ export function isosManager() {
     // ── Display helpers ───────────────────────────────────────────────────────
 
     isoFilename(volid) { return (volid || '').split('/').pop(); },
-    isoStorage(volid) { return (volid || '').split('/')[0] || ''; },
+    isoStorage(volid) { return (volid || '').split(':')[0] || ''; },
     isoSizeGB(iso) { return iso.size ? (iso.size / 1073741824).toFixed(2) : 'Unknown'; },
     vmMemGB(vm) { return vm.maxmem ? (vm.maxmem / 1073741824).toFixed(1) : 'Unknown'; },
     vmCpuInfo(vm) { return vm.cpus ? `${vm.cpus} cores` : 'Unknown'; },