When using organic feed, the growth could be even slower as some of the beneficial bacteria and fungi are still getting setup, particularly the Bactrex. It is not unusual to see some yellowing on leaves early due to the time it takes for the organic material into nutrients to happening smoothly. It seems like you have the rest of your environment dialed in pretty well, so as long as you aren't over-watering (which is 1 of the most common mistakes), you look to be in very good shape. Many growers leave their tap water out overnight as well to dissipate any chlorine in your water, not sure if you are doing that. According to bio tabs feed schedule, you don't need to PH your water, as you are not feeding the plant, but the soil, the beneficial bacteria, and fungi which in turn supply the nutrients.
Good luck and Happy growing!! 💪