Ph in 6.0, Ph out 4.6

[silverhaze]

Week three Flower; I'm top feeding rockwool cubes on cocomat in trays draining to waste. Since the switch, the plants have shown various deficiencies like calcium, mg and trace elements. In this new version I can't find my photos but I have uploaded them to my page. Light green/yellow tops, spotting on lower leaf edges. Regardless, the ultimate question is why is the ph coming out so low and what can be done about it. Mix is basic GH 3 part with calmag, sweet, monster bloom.

Thank you for your help..

 

[silverhaze]

Follow up, here's a picture from today. We flushed a week ago today since then the tops look slightly better the lower leaves have continued to yellow and curl.