Fix issue with plumbing reaction chambers getting stuck filling

code/datums/components/plumbing/_plumbing.dm

@@ -66,9 +66,14 @@
 		var/datum/component/plumbing/supplier = A
 		if(supplier.can_give(amount, reagent, net))
 			valid_suppliers += supplier
+	// Need to ask for each in turn very carefully, making sure we get the total volume. This is to avoid a division that would always round down and become 0
+	var/targetVolume = reagents.total_volume = amount
+	var/suppliersLeft = valid_suppliers.len
 	for(var/A in valid_suppliers)
 		var/datum/component/plumbing/give = A
-		give.transfer_to(src, amount / valid_suppliers.len, reagent, net)
+		var/currentRequest = (targetVolume - reagents.total_volume) / suppliersLeft
+		give.transfer_to(src, currentRequest, reagent, net)
+		suppliersLeft--
 ///returns TRUE when they can give the specified amount and reagent. called by process request
 /datum/component/plumbing/proc/can_give(amount, reagent, datum/ductnet/net)
 	if(amount <= 0)

code/datums/components/plumbing/reaction_chamber.dm

@@ -23,7 +23,7 @@
 			var/datum/reagent/RD = A
 			if(RT == RD.type)
 				has_reagent = TRUE
-				if(RD.volume < RC.required_reagents[RT])
+				if(RD.volume + CHEMICAL_QUANTISATION_LEVEL < RC.required_reagents[RT]) // Allow the chamber to exit filling mode when it feels it has enough even if short by a tiny fraction
 					process_request(min(RC.required_reagents[RT] - RD.volume, MACHINE_REAGENT_TRANSFER) , RT, dir)
 					return
 		if(!has_reagent)