I have my salt mixing station in my garage. I pump both Salt mix and RO/DI water above the ceiling, across rafters and down into my "fish room" (extra closet) behind the wall where my Display tank is. Inside the fish room I have 2 acrylic reservoir, 10 gal. for salt and 5 gal. for RO water. The reason I do this is here in S. Florida my garage temp. runs 85-95 deg. in the summer, so having the holding reservoirs inside I can store it at room temp. My question; is there a way or technique to pre-dose or treat my water before I send it to ATO or Auto Water change via my DOS. I have read about adding Kalk to the ATO container and slowly add via top off. I have a small circulating pump in the Salt water reservoir running and was wondering if there is any benefit to supplementing or pre-dosing my salt or RO water while in the holding container? I currently dose Red Sea foundation to my sump, but I always wondered if anyone has pre-supplemented there water?