diff --git a/_maps/map_files/RandomZLevels/evil_santa.dmm b/_maps/map_files/RandomZLevels/evil_santa.dmm
index ff5d4df54b9..0a92eaa1b29 100644
--- a/_maps/map_files/RandomZLevels/evil_santa.dmm
+++ b/_maps/map_files/RandomZLevels/evil_santa.dmm
@@ -650,7 +650,7 @@
 /area/awaymission/challenge/start)
 "bT" = (
 /obj/structure/dispenser/oxygen{
-	oxygentanks = 9
+	starting_oxygen_tanks = 9
 	},
 /obj/machinery/atmospherics/pipe/simple/hidden/scrubbers,
 /turf/simulated/floor/plasteel,
diff --git a/_maps/map_files/RandomZLevels/moonoutpost19.dmm b/_maps/map_files/RandomZLevels/moonoutpost19.dmm
index affcac8c979..26ff48b4d88 100644
--- a/_maps/map_files/RandomZLevels/moonoutpost19.dmm
+++ b/_maps/map_files/RandomZLevels/moonoutpost19.dmm
@@ -2432,7 +2432,7 @@
 	})
 "dy" = (
 /obj/structure/dispenser/oxygen{
-	oxygentanks = 9
+	starting_oxygen_tanks = 9
 	},
 /obj/machinery/light/small{
 	active_power_usage = 0;
diff --git a/code/game/objects/structures/tank_dispenser.dm b/code/game/objects/structures/tank_dispenser.dm
index 854bc18ce00..692d15d79ec 100644
--- a/code/game/objects/structures/tank_dispenser.dm
+++ b/code/game/objects/structures/tank_dispenser.dm
@@ -1,3 +1,5 @@
+#define MAX_TANK_STORAGE	10
+
 /obj/structure/dispenser
 	name = "tank storage unit"
 	desc = "A simple yet bulky storage device for gas tanks. Has room for up to ten oxygen tanks, and ten plasma tanks."
@@ -5,29 +7,51 @@
 	icon_state = "dispenser"
 	density = 1
 	anchored = 1.0
-	var/oxygentanks = 10
-	var/plasmatanks = 10
-	var/list/oxytanks = list()	//sorry for the similar var names
-	var/list/platanks = list()
+	var/starting_oxygen_tanks = MAX_TANK_STORAGE // The starting amount of oxygen tanks the dispenser gets when it's spawned
+	var/starting_plasma_tanks = MAX_TANK_STORAGE // Starting amount of plasma tanks
+	var/list/stored_oxygen_tanks = list() // List of currently stored oxygen tanks
+	var/list/stored_plasma_tanks = list() // And plasma tanks
 
 /obj/structure/dispenser/oxygen
-	plasmatanks = 0
+	starting_plasma_tanks = 0
 
 /obj/structure/dispenser/plasma
-	oxygentanks = 0
+	starting_oxygen_tanks = 0
 
 /obj/structure/dispenser/New()
 	..()
+	initialize_tanks()
 	update_icon()
 
+/obj/structure/dispenser/Destroy()
+	QDEL_LIST(stored_plasma_tanks)
+	QDEL_LIST(stored_oxygen_tanks)
+	return ..()
+
+/obj/structure/dispenser/proc/initialize_tanks()
+	for(var/I in 1 to starting_plasma_tanks)
+		var/obj/item/tank/plasma/P = new(src)
+		stored_plasma_tanks.Add(P)
+
+	for(var/I in 1 to starting_oxygen_tanks)
+		var/obj/item/tank/oxygen/O = new(src)
+		stored_oxygen_tanks.Add(O)
+
 /obj/structure/dispenser/update_icon()
-	overlays.Cut()
-	switch(oxygentanks)
-		if(1 to 3)	overlays += "oxygen-[oxygentanks]"
-		if(4 to INFINITY) overlays += "oxygen-4"
-	switch(plasmatanks)
-		if(1 to 4)	overlays += "plasma-[plasmatanks]"
-		if(5 to INFINITY) overlays += "plasma-5"
+	cut_overlays()
+	var/oxy_tank_amount = LAZYLEN(stored_oxygen_tanks)
+	switch(oxy_tank_amount)
+		if(1 to 3)
+			overlays += "oxygen-[oxy_tank_amount]"
+		if(4 to INFINITY)
+			overlays += "oxygen-4"
+
+	var/pla_tank_amount = LAZYLEN(stored_plasma_tanks)
+	switch(pla_tank_amount)
+		if(1 to 4)
+			overlays += "plasma-[pla_tank_amount]"
+		if(5 to INFINITY)
+			overlays += "plasma-5"
 
 /obj/structure/dispenser/attack_hand(mob/user)
 	if(..())
@@ -38,7 +62,7 @@
 /obj/structure/dispenser/attack_ghost(mob/user)
 	ui_interact(user)
 
-/obj/structure/dispenser/ui_interact(mob/user, ui_key = "main", datum/nanoui/ui = null, force_open = 1, var/master_ui = null, var/datum/topic_state/state = GLOB.default_state)
+/obj/structure/dispenser/ui_interact(mob/user, ui_key = "main", datum/nanoui/ui = null, force_open = 1, master_ui = null, datum/topic_state/state = GLOB.default_state)
 	user.set_machine(src)
 	ui = SSnanoui.try_update_ui(user, src, ui_key, ui, force_open)
 	if(!ui)
@@ -47,35 +71,19 @@
 
 /obj/structure/dispenser/ui_data(user)
 	var/list/data = list()
-	data["o_tanks"] = oxygentanks
-	data["p_tanks"] = plasmatanks
+	data["o_tanks"] = LAZYLEN(stored_oxygen_tanks)
+	data["p_tanks"] = LAZYLEN(stored_plasma_tanks)
 	return data
 
 /obj/structure/dispenser/attackby(obj/item/I, mob/user, params)
 	if(istype(I, /obj/item/tank/oxygen) || istype(I, /obj/item/tank/air) || istype(I, /obj/item/tank/anesthetic))
-		if(oxygentanks < 10)
-			user.drop_item()
-			I.forceMove(src)
-			oxytanks.Add(I)
-			oxygentanks++
-			update_icon()
-			to_chat(user, "<span class='notice'>You put [I] in [src].</span>")
-		else
-			to_chat(user, "<span class='notice'>[src] is full.</span>")
-		SSnanoui.update_uis(src)
+		try_insert_tank(user, stored_oxygen_tanks, I)
 		return
+
 	if(istype(I, /obj/item/tank/plasma))
-		if(plasmatanks < 10)
-			user.drop_item()
-			I.forceMove(src)
-			platanks.Add(I)
-			plasmatanks++
-			update_icon()
-			to_chat(user, "<span class='notice'>You put [I] in [src].</span>")
-		else
-			to_chat(user, "<span class='notice'>[src] is full.</span>")
-		SSnanoui.update_uis(src)
+		try_insert_tank(user, stored_plasma_tanks, I)
 		return
+
 	if(istype(I, /obj/item/wrench))
 		if(anchored)
 			to_chat(user, "<span class='notice'>You lean down and unwrench [src].</span>")
@@ -88,40 +96,55 @@
 
 /obj/structure/dispenser/Topic(href, href_list)
 	if(..())
-		return 1
+		return TRUE
 
 	if(Adjacent(usr))
 		usr.set_machine(src)
+
+		// The oxygen tank button
 		if(href_list["oxygen"])
-			if(oxygentanks > 0)
-				var/obj/item/tank/oxygen/O
-				if(oxytanks.len == oxygentanks)
-					O = oxytanks[1]
-					oxytanks.Remove(O)
-				else
-					O = new /obj/item/tank/oxygen(loc)
-				O.loc = loc
-				to_chat(usr, "<span class='notice'>You take [O] out of [src].</span>")
-				oxygentanks--
-				update_icon()
+			try_remove_tank(usr, stored_oxygen_tanks)
+
+		// The plasma tank button
 		if(href_list["plasma"])
-			if(plasmatanks > 0)
-				var/obj/item/tank/plasma/P
-				if(platanks.len == plasmatanks)
-					P = platanks[1]
-					platanks.Remove(P)
-				else
-					P = new /obj/item/tank/plasma(loc)
-				P.loc = loc
-				to_chat(usr, "<span class='notice'>You take [P] out of [src].</span>")
-				plasmatanks--
-				update_icon()
+			try_remove_tank(usr, stored_plasma_tanks)
+
 		add_fingerprint(usr)
 		updateUsrDialog()
-		SSnanoui.update_uis(src)
+		SSnanoui.try_update_ui(usr, src)
 	else
 		SSnanoui.close_user_uis(usr,src)
-	return 1
+	return TRUE
+
+/// Called when the user clicks on the oxygen or plasma tank UI buttons, and tries to withdraw a tank.
+/obj/structure/dispenser/proc/try_remove_tank(mob/living/user, list/tank_list)
+	if(!LAZYLEN(tank_list))
+		return // There are no tanks left to withdraw.
+
+	var/obj/item/tank/T = tank_list[1]
+	tank_list.Remove(T)
+
+	if(!user.put_in_hands(T))
+		T.forceMove(loc) // If the user's hands are full, place it on the tile of the dispenser.
+
+	to_chat(user, "<span class='notice'>You take [T] out of [src].</span>")
+	update_icon()
+
+/// Called when the user clicks on the dispenser with a tank. Tries to insert the tank into the dispenser, and updates the UI if successful.
+/obj/structure/dispenser/proc/try_insert_tank(mob/living/user, list/tank_list, obj/item/tank/T)
+	if(LAZYLEN(tank_list) >= MAX_TANK_STORAGE)
+		to_chat(user, "<span class='warning'>[src] is full.</span>")
+		return
+
+	if(!user.drop_item()) // Antidrop check
+		to_chat(user, "<span class='warning'>[T] is stuck to your hand!</span>")
+		return
+
+	T.forceMove(src)
+	tank_list.Add(T)
+	update_icon()
+	to_chat(user, "<span class='notice'>You put [T] in [src].</span>")
+	SSnanoui.try_update_ui(user, src)
 
 /obj/structure/tank_dispenser/deconstruct(disassembled = TRUE)
 	if(!(flags & NODECONSTRUCT))
@@ -130,3 +153,5 @@
 			I.forceMove(loc)
 		new /obj/item/stack/sheet/metal(loc, 2)
 	qdel(src)
+
+#undef MAX_TANK_STORAGE