Seedsman White Widow

Lots of LST and pruning this last week. PH has been dropping which is a concern. 2019-11-11 - Needed 2 liters of water top up. The filtered water had a base ppm of 156. I brought the ph down to 6. The res water BEFORE topping up had a ppm of 320 and a ph of 5-5.5. Did a lot of pruning. 2019-11-12 - ppm of 240 ph of 5 2019-11-13 - res water had 225ppm and ph of around 4.5 :| Topped up with 2 liters of water that started with a ppm of 134. I didn't ph down the water, hoping to offset the low ph that is currently in the res. I added 5cc of grow big and 10cc of big bloom to 1.5 gallons of water to be split amongst plants 2 liters of this water was used to top up the white widow res and had a ppm of 428. Increased the nute ratio a bit since the last week the ppm has been dropping. The low ph is a concern so I added a cap full of h2o2