Your adding the cal mag wrong. When your RO water comes out it will be at around 7.0 pH and 10-30 ppm depending on its efficiency. In a mater of minutes that ph will drop to 6.0 to 6.5 due to carbon dioxide in the air interacting with the water molecules creating carbonic acid. First thing you should do is add the cal mag until your ppm reaches 160 ppm to create a nice buffer for your nutrients. Then mix in your fertilizers and let it rest for about 10 minutes. After that adjust your ph to 5.8 to 6.2 depending on whether it tends to drift up or down. (5.8 if it goes up, 6.2 if it goes down, usually it goes down if using co2. Then just apply it to your plants. Don't follow the instructions on bottles when it comes to how much to use, judge it based on your plants. The directions on the bottles are usually the maximum amount possible to encourage you to use more of their products faster. Figure out how much cal mag you need to get your ppm to 150-160 if you can. I use about 2 ml per gallon of water and my ppm is at 150 before adding my nutrients. Typically the cal mag is used to buffer solutions and is only used in veg if it contains nitrogen. During veg you can get away with following the instructions on the bottle but even that is a little high. I go with half of what they recommend for hydroponics use and supplement the additional nutrients with AN grow parts A+B, b-52, voodoo juice, a little bud candy, and beneficial bacteria. You will never have another problem with nutrients if you learn how to use beneficial bacteria correctly and keep your ph correct.
