modular chemical reactions for hydroponics trays

code/modules/hydroponics/hydroponics.dm

@@ -534,8 +534,12 @@
 			if(istype(reagent_source, /obj/item/reagent_containers/food/snacks) || istype(reagent_source, /obj/item/reagent_containers/pill))
 				qdel(reagent_source)
 
-			if(S.on_tray(H, split, user) >= 1)
+			if(myseed)
+				myseed.on_chem_reaction(S)
 				lastuser = user
+			for(var/datum/reagent/R in S.reagent_list)
+				if(R.on_tray(H, R.volume, user) >= 1)
+					lastuser = user
 
 			S.clear_reagents()
 			qdel(S)

code/modules/integrated_electronics/subtypes/reagents.dm

@@ -36,10 +36,11 @@
 
 	for(var/obj/machinery/hydroponics/H in trays)
 		var/datum/reagents/temp_reagents = new /datum/reagents()
-		temp_reagents.my_atom = H
 
 		source.reagents.trans_to(temp_reagents, split)
-		H.applyChemicals(temp_reagents)
+		for(var/datum/reagent/R in temp_reagents.reagent_list)
+			if(R.on_tray(H, R.volume, src) >= 1)
+				tray.lastuser = src
 
 		temp_reagents.clear_reagents()
 		qdel(temp_reagents)

code/modules/reagents/chemistry/reagents.dm

@@ -78,8 +78,8 @@ GLOBAL_LIST_INIT(name2reagent, build_name2reagent())
 	return
 
 //Hyperstation Edit: Hydroponics trays reactions, idea stolen from citadel but not directly referenced
-/datum/reagent/proc/on_tray(/obj/machinery/hydroponics/T, volume, mob/user, override = FALSE)	//See hyperstation's reagent module
-	if(!tray.myseed)
+/datum/reagent/proc/on_tray(obj/machinery/hydroponics/T, volume, mob/user)	//See hyperstation's reagent module
+	if(!T.myseed)
 		return 0
 	return -1