when I was up north ,I would run it until pink came out and do not forget your water tank water pump
and water lines if you have a hot water tank it needs the pink stuff to. Get the kind they used to winterize rv and travel trailers,you can get it at westmarine if you have onenear you.I also put it in the head
. Get plenty, what you dont use this season you can use the rest next season and you will then know how much you will need bill.