I topped off the nutrient solution daily, and adjusted the minor ph fluctuation every other day. Generally, I noticed I was running between 5.8 and 5.5 and would have to only use a small amount of ph up to adjust the solution. This girl is not a big drinker. The night time temperature in my area has dropped to around 30f, so my nighttime tent temps are following suit, but still well within acceptable parameters. I will say that 5 plants in a 4.4 is too many for a DWC grow. In fact, I'm not sure I would want to grow more than 2 plants in DWC in the future. Time will tell.
Good luck! I have the same #10, the mother is thriving in veg even under minimal lighting as I have already taken a set off her and rooted them, and transplanted to 3.5". I need to update and publish my diary. Will do so in the next day or so. :) I'm following.