diff --git a/mods/solarmana/README.txt b/mods/solarmana/README.txt
index fe06b05e..5c6279f0 100755
--- a/mods/solarmana/README.txt
+++ b/mods/solarmana/README.txt
@@ -4,7 +4,7 @@ Solar Mana Mod [solarmana]
 A mana regeneration controller: only regenerate mana in sunlight
 or on special nodes.
 
-Version: 0.3.0
+Version: 0.4.0
 Licence: LGPL 2.1 or later
 
 Report bugs or request help on the forum topic.
@@ -21,6 +21,9 @@ Since many magic users prefer their homes and offices to actually
 have a roof, standing on specific node types (currently wooden
 planks and gold blocks) will also regenerate mana.
 
+Now with support for slower, and negative, regeneration. Just
+for fun, standing on stone will drain your mana...
+
 Dependencies
 ------------
 * mana: https://forum.minetest.net/viewtopic.php?f=11&t=11154
diff --git a/mods/solarmana/init.lua b/mods/solarmana/init.lua
index 163ded81..a2b21491 100755
--- a/mods/solarmana/init.lua
+++ b/mods/solarmana/init.lua
@@ -85,19 +85,28 @@ minetest.register_globalstep(function(dtime)
             -- next, check the block we're standing on.
             pos.y = math.floor(pos_y) - 0.5
             node = minetest.get_node(pos)
-            if mana_from_node[node.name] then
-                regen_to = math.max(regen_to, mana_from_node[node.name])
+            local nodemana = mana_from_node[node.name]
+            for key, value in pairs(mana_from_node) do
+                if key:split(":")[1] == "group" then
+                    local groupname = key:split(":")[2]
+                    if minetest.get_node_group(node.name, groupname) > 0 then
+                        if nodemana then
+                            nodemana = math.max(nodemana, value) -- We get the greater one (if the node is part of 2 or more groups)
+                        else
+                            nodemana = value
+                        end
+                    end
+                end
+            end
+            if nodemana then
+                if nodemana > 0 then
+                    regen_to = math.max(regen_to, nodemana)
+                else
+                    regen_to = regen_to + nodemana -- negative, remember?
+                end
                 --print("Regen to "..regen_to.." : "..node.name)
             end
 
-            for key, value in pairs(mana_from_node) do
-		if key:split(":")[1] == "group" then
-			local groupname = key:split(":")[2]
-			if minetest.get_node_group(node.name, groupname) > 0 then
-				regen_to = math.max(regen_to, value) -- We get the greater one (if the node is part of 2 or more groups)
-			end
-		end
-	    end
 
             mana.setregen(name, regen_to)
             --print("Regen to "..regen_to.." : "..light_day.."/"..light_now.."/"..light_night)