My leaves on plant getting yellow at week 4. Gave ...

Well , I've noticed a few things here that may help you with your yellowing leaves . I've noticed that your PH is fluctuating by a lot this isn't good and is going to lead to mega problems . The first thing you wanna do is correct that in a soiless mix your ideal PH is 6.2 - 6.4 this will prevent nutrient lock outs from happening so that your plant can absorb all the nutrients in your medium . Fluctuating your PH will also cause your plant to go into shock because 1 days its getting what it needs and the next its not and so on it also makes the root zone to "hot" , so its best you adjust your PH to a prime level and try to be as consistent as possible with it . Another reason you might be getting that yellow is from over watering a tip I can suggest to you is get yourself some saucers and bottom feed your plants this way the plant will only drink what it wants and leave the rest this will help BIG TIME in not over watering your plants although hard to do at later stages of its life it still can be over watered in its adult life . Last but not least your nutrient line , your in veg but your boosting the PK really really really hard your giving your plants the wrong food at this time . I would correct that and only boost PK when pre-flowers start to show in order to facilitate their growth . Once you adjust the nutrient feeding I would lower the dosage and add a little more CalMg . I hope the information provided here helps you !