i dont think i put the question right. if the ppm are at 1000 with 40 liters of water and after 5 days the plants have used 20lts of the water and its still at 1000ppm. then is this the right level of nutes. if the ppm dropped would this be under feeding and if it rises would this be a little to strong. or should your ppm always rise a little day to day.