HELP PLEASE HELP ME plants dying

im using an six plant dwc system with hesi hydro nutes
so heres the story
at three weeks into flower i did a res change filled it back up with tap water and ran out of bloom nutes and the hydro store was closed for the next two days
so i ran 350 ppm fir two days (originally at 1200 ppm) then i got the nutes from the store and brought it back up to 1200 ppm
and now three of the six plants are dying
the ph is at 5.6 by the way
please and help would be awesome

You gotta give us more info. What do you mean by "dying"? Did you pH the tap water when you ran out of nutes?

yea i did
the two bottom branches are turning light green then yellow and losing all the moisture and drying up and crumbling apart
and now its starting to happen to the rest of the plant.

Any pics? It sounds like lack of nitrogen (N). It is normal for leaves to yellow during flowering but it should not be rapid and they shouldn't crumble and die. Plus, it should be uniform throughout all your plants. Pics would really help.

seeing as you had it at 350ppm that would cause the plants to die because it is too looow so it takes a little time for these problems to become apparent so that is probably why the plant is eating the leaves because it was starved for several days. even shultz will work in dwc for future reference.