diff --git a/mods/ITEMS/mcl_mangrove/init.lua b/mods/ITEMS/mcl_mangrove/init.lua
index cf11f36ed..932e7851d 100644
--- a/mods/ITEMS/mcl_mangrove/init.lua
+++ b/mods/ITEMS/mcl_mangrove/init.lua
@@ -221,7 +221,7 @@ local wlroots = {
 	liquids_pointable = true,
 	drop = "mcl_mangrove:mangrove_roots",
 	groups = {
-		handy = 1, hoey = 1, water=3, liquid=3, puts_out_fire=1, dig_by_piston = 1, deco_block = 1,  not_in_creative_inventory=1 },
+		handy = 1, hoey = 1, water=3, liquid=3, puts_out_fire=1, dig_by_piston = 1, deco_block = 1, waterlogged = 1, not_in_creative_inventory=1 },
 	_mcl_blast_resistance = 100,
 	_mcl_hardness = -1, -- Hardness intentionally set to infinite instead of 100 (Minecraft value) to avoid problems in creative mode
 	on_construct = function(pos)
diff --git a/mods/ITEMS/mcl_ocean/kelp.lua b/mods/ITEMS/mcl_ocean/kelp.lua
index 1084dfa77..530d96093 100644
--- a/mods/ITEMS/mcl_ocean/kelp.lua
+++ b/mods/ITEMS/mcl_ocean/kelp.lua
@@ -267,7 +267,8 @@ function kelp.next_height(pos, node, pos_tip, node_tip, submerged, downward_flow
 	-- Flowing liquid: Grow 1 step, but also turn the tip node into a liquid source.
 	if downward_flowing then
 		local alt_liq = mt_registered_nodes[node_tip.name].liquid_alternative_source
-		if alt_liq then
+		local alt_liq_accessible = mt_get_item_group(node_tip.name,"waterlogged") -- returns 0 if it isn't waterlogged.
+		if alt_liq and not alt_liq_accessible then
 			mt_set_node(pos_tip, {name=alt_liq})
 		end
 	end
diff --git a/mods/ITEMS/mcl_sponges/init.lua b/mods/ITEMS/mcl_sponges/init.lua
index e9755479b..87f40e3ae 100644
--- a/mods/ITEMS/mcl_sponges/init.lua
+++ b/mods/ITEMS/mcl_sponges/init.lua
@@ -155,7 +155,7 @@ minetest.register_node("mcl_sponges:sponge_wet", {
 	buildable_to = false,
 	stack_max = 64,
 	sounds = mcl_sounds.node_sound_dirt_defaults(),
-	groups = {handy=1, hoey=1, building_block=1},
+	groups = {handy=1, hoey=1, waterlogged = 1, building_block=1},
 	on_place = place_wet_sponge,
 	_mcl_blast_resistance = 0.6,
 	_mcl_hardness = 0.6,
@@ -175,7 +175,7 @@ if minetest.get_modpath("mclx_core") then
 		buildable_to = false,
 		stack_max = 64,
 		sounds = mcl_sounds.node_sound_dirt_defaults(),
-		groups = {handy=1, building_block=1},
+		groups = {handy=1, waterlogged = 1, building_block=1},
 		on_place = place_wet_sponge,
 		_mcl_blast_resistance = 0.6,
 		_mcl_hardness = 0.6,