Okay peeps I need some input again. I have no sump with this nano (for now). I want to use Kalk in my system. I do not have a top off system in place and I am not sure I ever will because they worry me a bit (just a me thang) Here is my question. Starting out if I cut my dose down to 1 tsp. per 5 gallons of RO water and used this as top off water would it be okay? The normal dosage is 2 tsp. per 5 gallons of water that you are mixing. I had to manually put in some top off RO water this morning and it was probably maybe 4 cups or so lets say. If I had used my pre disolved Kalk RO water for that top off would it have been okay? The Kalk I will be using is Kent powder mix. I know that Kalk can be awesome as a supplement when used correctly but I have never used it. I may later on figure out a way to have a sump with this system and then dose the Kalk that way but until then I am just making sure my plan would be okay. Let me know what you guys think please.