ppm of water + nut ppm= desired?....

OK I'll try to make this simple... If you're water measures in at 100 ppm and I'm going for a 800 ppm nute mix for my plants.. Should you add that to get 900 for the total ppm of the solution, or should whats already in the water just be added as part of the total ppm goal giving you 800?

what you should do is let the water sit for a day or two. chlorine evaporates and leaves your water at 0 ppm. if youre aiming for 800 then thats the total, because you have to make sure the solution isnt too thick. this doesnt refer to the amount of nutrients, but all solids in the water, so its good to make sure you dont have anything in there that you dont want, like chlorine

OR if you are like me and don't want to wait just take that 900 ppm as 800 ppm and you are good. been doing it w/ 120-150 ppm out the tap for many many years w/ excellent results. ideally you want to wait but honestly.... I never noticed a difference.