4th week of veg of green crack punch problems

Hello I have 3 green crack punch one looks awesome and the one looks sick I did a ph runoff and it was a 5 just watered them a day with just plain tap water with a 6.5 ph to try to increase it what else can I do? I use earth juice and have sunshine #4 mix with soil and black Kow fertilizer. Thank you

Raise the ph of your input mix to 7.2. Add dolomite lime to your soil mix next time. 1/4 cup per 5 gallons of soil