diff --git a/mods/default/nodes.lua b/mods/default/nodes.lua
index c70f614b..db679830 100644
--- a/mods/default/nodes.lua
+++ b/mods/default/nodes.lua
@@ -2078,6 +2078,7 @@ minetest.register_node("default:glass", {
 	drawtype = "glasslike_framed_optional",
 	tiles = {"default_glass.png", "default_glass_detail.png"},
 	paramtype = "light",
+	paramtype2 = "glasslikeliquidlevel",
 	sunlight_propagates = true,
 	is_ground_content = false,
 	groups = {cracky = 3, oddly_breakable_by_hand = 3},
@@ -2089,6 +2090,7 @@ minetest.register_node("default:obsidian_glass", {
 	drawtype = "glasslike_framed_optional",
 	tiles = {"default_obsidian_glass.png", "default_obsidian_glass_detail.png"},
 	paramtype = "light",
+	paramtype2 = "glasslikeliquidlevel",
 	is_ground_content = false,
 	sunlight_propagates = true,
 	sounds = default.node_sound_glass_defaults(),