Blue Dream + Bubba Kush

Well best amd probably only way is to have an ec meter. Ppm's are converted numbers from ec thats measured and differing from manufacturer the ec is multiplied by 500,600 or 700 to get the PPM's

If you choose to measure by PPM, hydro growers should begin with a solution that has 500 PPM and increase by 50 every week. The pH should be close to 5.5, and at least 5.2. Any nutrient with less than 200 PPM will be very light. Hope this helps.. Happy growing! 👊