diff --git a/README.md b/README.md
index 3373b84..2db84cc 100644
--- a/README.md
+++ b/README.md
@@ -7,18 +7,18 @@
 
 This mod features three tiers of air filtering machines. These machines remove pollution from the air in their region by using air filters. Each consecutive tier has a larger radius and stronger filtering effect. Keep in mind that you will still need filters spread around your base at strategic locations to effectively counteract the spread of pollution.  
 
-#### Air filter machine 1
+### Air filter machine 1
 You start with a basic passive air filter machine that cleans the air in its own [chunk](https://wiki.factorio.com/Map_structure#Chunk). It should help keep biter attacks at bay through the early game.
 
-#### Air filter machine 2
+### Air filter machine 2
 The upgraded version has a stronger filtering effect. In addition, by using a moderate amount of electricity this machine is able to pull in pollution from neighboring chunks in the shape of a diamond. This version has a radius of two chunks (in [manhattan distance](https://en.wikipedia.org/wiki/Taxicab_geometry)). Note that a continuous amount of energy is consumed for this suction effect in addition to the cost of filtering the air.
 
 ![range_mark_2](https://github.com/JoeyDP/Factorio-Better-Air-Filtering/blob/master/res/radius_mk2.png?raw=true)
 
-#### Air filter machine 3
+### Air filter machine 3
 The third and final upgrade of the air filtering machine features a larger radius of three chunks along with more air filtering per second.
 
-#### Filter Types
+### Filter Types
 There are currently two types of filters: __expendable filters__ and __recyclable filters__. The first ones are easier to craft, but filter out less pollution and are destroyed upon use. Recyclable filters are more expensive but can be refreshed with a bit of coal to be used again.
 
 > Known issue: used air filters cannot be extracted from the first tier of air filter machines by inserters. Factorio does not feature inserters that can extract from burnt_result_inventory.
diff --git a/better-air-filtering/changelog.txt b/better-air-filtering/changelog.txt
index dd5b97c..4889ff9 100644
--- a/better-air-filtering/changelog.txt
+++ b/better-air-filtering/changelog.txt
@@ -7,3 +7,11 @@ Date: 2019.10.08
     - Only English
   License:
     - Using MIT License.
+---------------------------------------------------------------------------------------------------
+Version: 0.1.1
+Date: 2019.10.09
+  Features:
+    - Pollution is now registered in the pollution statistics rather than the fluid statistics.
+    - Air filter machines now accept speed and efficiency modules or beacon effects.
+  Fixes:
+    - Invalid entity issue when removing air filter machine during update resolved.
diff --git a/better-air-filtering/control.lua b/better-air-filtering/control.lua
index f8bdf12..b9eaa50 100644
--- a/better-air-filtering/control.lua
+++ b/better-air-filtering/control.lua
@@ -38,13 +38,6 @@ function positionToChunk(position)
     return { x = math.floor(position.x / 32), y = math.floor(position.y / 32) }
 end
 
-function movePollution(surface, chunkFrom, chunkTo, amount)
-    amount = math.min(amount, surface.get_pollution(chunkToPosition(chunkFrom)))
-    surface.pollute(chunkToPosition(chunkFrom), -amount)
-    surface.pollute(chunkToPosition(chunkTo), amount)
-    return amount
-end
-
 function getBasePurificationRate(entity)
     -- Depends mostly on recipe (optimal recipe used per machine). Should be multiplied by crafting speed to achieve actual max purification rate
     if entity.name == "air-filter-machine-1" then
@@ -176,10 +169,11 @@ function absorbChunk(chunk)
     --    game.print("To absorb: " .. toAbsorb)
 
     local totalInsertedAmount = 0.0
-    for _, filter in pairs(chunk.filters) do
+    for _, filter in pairs(chunk:getFilters()) do
         local toInsert = (getAbsorptionRate(filter) / totalAbsorptionRate) * toAbsorb
         if toInsert > 0 then
             local insertedAmount = filter.insert_fluid({ name = "pollution", amount = toInsert })
+            game.pollution_statistics.on_flow(filter.name, -insertedAmount)
             totalInsertedAmount = totalInsertedAmount + insertedAmount
         end
     end
@@ -332,13 +326,14 @@ local FilteredChunk = {
     surface = nil,
     x = 0,
     y = 0,
-    filters = {},
+    --filters = {}
 }
 
 function FilteredChunk:new (o)
     o = o or {}
     setmetatable(o, self)
     self.__index = self
+    o.filters = o.filters or {}
     return o
 end
 
@@ -347,7 +342,6 @@ function createFilteredChunk(surface, x, y)
     chunk.surface = surface
     chunk.x = x
     chunk.y = y
-    chunk.filters = {}      -- this statement, though it appears to have no effect, has a large impact on the saving of global state.
     return chunk
 end
 
@@ -355,7 +349,25 @@ function FilteredChunk:equal(other)
     return self.surface.name == other.surface.name and self.x == other.x and self.y == other.y
 end
 
+function FilteredChunk:getFilters()
+    local filters = {}
+    for _, filter in pairs(self.filters) do
+        if filter.valid then
+            table.insert(filters, filter)
+        end
+    end
+    self.filters = filters
+    return filters
+end
+
 function FilteredChunk:addToMap()
+
+    --game.print("Active chunks before: ")
+    --for i, c in pairs(air_filtered_chunks) do
+    --    game.print(serpent.line(c))
+    --end
+    --game.print(serpent.block(global.air_filtered_chunks_map))
+
     --game.print("Adding chunk to map")
     local chunkListX = global.air_filtered_chunks_map[self.surface.name] or {}
     local chunkListY = chunkListX[self.x] or {}
@@ -364,23 +376,47 @@ function FilteredChunk:addToMap()
     chunkListX[self.x] = chunkListY
     global.air_filtered_chunks_map[self.surface.name] = chunkListX
     table.insert(air_filtered_chunks, self)
+
+
+    --game.print("Active chunks after: ")
+    --for i, c in pairs(air_filtered_chunks) do
+    --    game.print(serpent.line(c))
+    --end
+    --game.print(serpent.block(global.air_filtered_chunks_map))
 end
 
 function FilteredChunk:removeFromMap()
     --game.print("Removing chunk from map")
-    table.remove(global.air_filtered_chunks_map[self.surface.name][self.x], self.y)
+    global.air_filtered_chunks_map[self.surface.name][self.x][self.y] = nil
+
     for i, c in pairs(air_filtered_chunks) do
         if self:equal(c) then
-            table.remove(air_filtered_chunks, i)
             --game.print("Removing chunk from list")
+            table.remove(air_filtered_chunks, i)
             break
         end
     end
+
+    --local i = 1
+    --while i <= #air_filtered_chunks do
+    --    local c = air_filtered_chunks[i]
+    --    if self:equal(c) then
+    --        --game.print("Removing chunk from list")
+    --        table.remove(air_filtered_chunks, i)
+    --    else
+    --        i = i + 1
+    --    end
+    --end
+
+    --game.print("Remaining chunks: ")
+    --for _, c in pairs(air_filtered_chunks) do
+    --    game.print(serpent.line(c))
+    --end
 end
 
 function FilteredChunk:getTotalAbsorptionRate()
     local totalAbsorptionRate = 0.0
-    for _, filter in pairs(self.filters) do
+    for _, filter in pairs(self:getFilters()) do
         local absorptionRate = getAbsorptionRate(filter)
         totalAbsorptionRate = totalAbsorptionRate + absorptionRate
     end
@@ -389,7 +425,7 @@ end
 
 function FilteredChunk:getTotalSuctionRate(distance)
     local totalSuctionRate = 0.0
-    for _, filter in pairs(self.filters) do
+    for _, filter in pairs(self:getFilters()) do
         if inRadius(filter, distance) then
             local suctionRate = getSuctionRate(filter)
             totalSuctionRate = totalSuctionRate + suctionRate
@@ -498,6 +534,7 @@ function onEntityRemoved(event)
     if pollution > 0 then
         --game.print("Dispersing " .. pollution .. " pollution back")
         event.entity.surface.pollute(event.entity.position, pollution)
+        game.pollution_statistics.on_flow(event.entity.name, pollution)
     end
 end
 
@@ -522,6 +559,7 @@ function preEntityRemoved(event)
         if pollution > 0 then
             --game.print("Dispersing " .. pollution .. " pollution back")
             event.entity.surface.pollute(event.entity.position, pollution)
+            game.pollution_statistics.on_flow(event.entity.name, pollution)
         end
     end
 
diff --git a/better-air-filtering/info.json b/better-air-filtering/info.json
index 2459ff5..e39f332 100644
--- a/better-air-filtering/info.json
+++ b/better-air-filtering/info.json
@@ -1,6 +1,6 @@
 {
   "name": "better-air-filtering",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "title": "Better Air Filtering",
   "author": "Joey De Pauw",
   "contact": "joeydepauw@gmail.com",
diff --git a/better-air-filtering/locale/en/air-filtering.cfg b/better-air-filtering/locale/en/air-filtering.cfg
index 571cc6f..93f5a47 100644
--- a/better-air-filtering/locale/en/air-filtering.cfg
+++ b/better-air-filtering/locale/en/air-filtering.cfg
@@ -5,8 +5,8 @@ air-filter-machine-3=Air filter machine 3
 
 [entity-description]
 air-filter-machine-1=Passive air filter that reduces pollution in the current chunk using air filters.
-air-filter-machine-2=A stronger air filter that uses electricity to pull pollution towards it from a 2 chunk radius.
-air-filter-machine-3=An even stronger air filter, capable of cleaning pollution in a 3 chunk radius.
+air-filter-machine-2=An air filter machine that uses electricity to pull pollution towards it from a 2 chunk radius.
+air-filter-machine-3=Powerful air filter, capable of cleaning pollution in a 3 chunk radius.
 
 
 [item-name]
diff --git a/better-air-filtering/migrations/0.1.1.lua b/better-air-filtering/migrations/0.1.1.lua
new file mode 100644
index 0000000..c456141
--- /dev/null
+++ b/better-air-filtering/migrations/0.1.1.lua
@@ -0,0 +1,9 @@
+for surfaceName, chunkListX in pairs(global.air_filtered_chunks_map) do
+    for x, chunkListY in pairs(chunkListX) do
+        for y, chunk in pairs(chunkListY) do
+            if chunk.filters == nil or #chunk.filters == 0 then
+                global.air_filtered_chunks_map[surfaceName][x][y] = nil
+            end
+        end
+    end
+end
diff --git a/better-air-filtering/prototypes/entity.lua b/better-air-filtering/prototypes/entity.lua
index bb51cb1..2147e5b 100644
--- a/better-air-filtering/prototypes/entity.lua
+++ b/better-air-filtering/prototypes/entity.lua
@@ -72,7 +72,10 @@ data:extend({
         fixed_recipe = "filter-air",
         ingredient_count = 1,
         return_ingredients_on_change = true,
-        module_slots = 0,
+        module_specification =
+        {
+            module_slots = 0
+        },
         allowed_effects=nil
     },
     {
@@ -162,9 +165,12 @@ data:extend({
         energy_usage = "50kW",
         fixed_recipe = "filter-air2",
         ingredient_count = 2,
+        module_specification =
+        {
+            module_slots = 2
+        },
+        allowed_effects = {"consumption", "speed"},
         return_ingredients_on_change = true,
-        module_slots = 0,
-        allowed_effects=nil
     },
     {
         type = "assembling-machine",
@@ -251,8 +257,12 @@ data:extend({
         energy_usage = "100kW",
         fixed_recipe = "filter-air2",
         ingredient_count = 2,
+        module_specification =
+        {
+            module_slots = 3
+        },
+        allowed_effects = {"consumption", "speed"},
         return_ingredients_on_change = true,
         module_slots = 0,
-        allowed_effects=nil
     }
 })
diff --git a/better-air-filtering/prototypes/recipe.lua b/better-air-filtering/prototypes/recipe.lua
index 16ba3af..fadb072 100644
--- a/better-air-filtering/prototypes/recipe.lua
+++ b/better-air-filtering/prototypes/recipe.lua
@@ -109,6 +109,7 @@ data:extend({
         type = "recipe",
         name = "filter-air",
         hide_from_player_crafting = true,
+        hide_from_stats = true,
         icons = {
             {
                 icon = "__base__/graphics/icons/fluid/pollution.png"
@@ -135,6 +136,7 @@ data:extend({
         type = "recipe",
         name = "filter-air2",
         hide_from_player_crafting = true,
+        hide_from_stats = true,
         icons = {
             {
                 icon = "__base__/graphics/icons/fluid/pollution.png"
@@ -163,6 +165,7 @@ data:extend({
         type = "recipe",
         name = "liquid-pollution",
         hide_from_player_crafting = true,
+        hide_from_stats = true,
         category = "air-filtering-advanced",
         subgroup = "raw-material",
         order = "c[filter-air]",