diff --git a/fluid_lib/buffer.lua b/fluid_lib/buffer.lua
index e541e7d..2c24d65 100644
--- a/fluid_lib/buffer.lua
+++ b/fluid_lib/buffer.lua
@@ -87,8 +87,8 @@ end
 
 function fluid_lib.insert_into_buffer(pos, buffer, fluid, count)
 	local bfdata = fluid_lib.get_buffer_data(pos, buffer)
-	if not bfdata then return 0 end
-	if bfdata.fluid ~= fluid and bfdata.fluid ~= "" then return 0 end
+	if not bfdata then return count end
+	if bfdata.fluid ~= fluid and bfdata.fluid ~= "" then return count end
 
 	local can_put = fluid_lib.can_insert_into_buffer(pos, buffer, fluid, count)
 
diff --git a/fluid_lib/nodeio.lua b/fluid_lib/nodeio.lua
index 712f10d..c37d7e6 100644
--- a/fluid_lib/nodeio.lua
+++ b/fluid_lib/nodeio.lua
@@ -52,7 +52,7 @@ local nodeiodef = {
 			local storage = bfdata.amount
 			local fluid = bfdata.fluid
 			if (fluid == want_liquid or want_liquid == "") and storage >= want_millibuckets then
-				name,took = fluid_lib.take_from_buffer(pos, buffer, want_millibuckets)
+				name, took = fluid_lib.take_from_buffer(pos, buffer, want_millibuckets)
 				if took > 0 then break end
 			end
 		end
@@ -75,6 +75,7 @@ local nodeiodef = {
 		for buf in pairs(bfs) do
 			cnt[#cnt + 1] = buf
 		end
+		if not cnt[index] then return ItemStack(nil) end
 		local meta = minetest.get_meta(pos)
 
 		return meta:get_string(cnt[index] .. "_fluid")
@@ -86,6 +87,7 @@ local nodeiodef = {
 		for buf in pairs(bfs) do
 			cnt[#cnt + 1] = buf
 		end
+		if not cnt[index] then return ItemStack(nil) end
 		local meta = minetest.get_meta(pos)
 
 		return ItemStack(meta:get_string(cnt[index] .. "_fluid") .. " " ..