Purple Haze Issues any assistance appreciated

Started Purple Haze from seed and moved them into grow tent.
Using 600 watt LED light along with Fans and extractors.
Starting the 4th week of flowering, went away for four days initiated an automatic watering system for every two days, two minutes.
Got back and noticed the new leaves are smaller and there is black/dark spots across many leaves.
Also noticed red/purple lines on some stalks.
I figured it was a phosphorus deficiency so i doused them with Phosphorus tea and slow release phosphorus.
Also raised LED from 12 inches to 18 inches.

Not sure if i got it right and any help is appreciated. Photos in link.
https://www.icmag.com/ic/photo_popup.php?e=vB_Editor_001#

Too much water maybe?

I was wondering that as well. I am monitoring water and it is putting out about 1 litre per plant every second day, they are dry to about 1 inch deep by the time watering starts in two days. I am using 5 gallon air pots and i started with supersoil in bottom 1/3 of pot.