DWC cal or P/k def?

[Perpagater]

hey guys hoping to get some good opinions here. these just went under HID lighting about a week ago and have started appearing deficient . they are very green but are getting rust looking spots with lighter patches.

they are on floranova bloom +cal mag. i recently moved and was away from them so im not sure about the exact ratio of cal mag i have put in recently . using mostly reverse osmosis water at 10ppm. occasional tapwater adback to raise ph.

the last 2 pictures are from today, i raised the ppms up to 1600 last night and i think the darker brown spots are slight burn. i have already backed off a little bit but im really wondering about the light rust spots.

i have already checked for mites/bugs they are clean. res temps are 67-71 degrees air temp 67(night)-75. roots look good ph is totally stable 5.4 , been adding some tapwater to try to up it. right now ppm at 1590-1600 and i have been adding about 15ml cal mag per 5gallon addback. havnt added PH up or down in over a month. (waterfall keeps it stable). i have a large res so changing it all out right now is not really an option.

[TBuds]

Cal is locked out @ 5.3 and mybe light burn,,and u said ur @ 5.4. Might have something to do with it. Good Luck

[5starfarmer]

Yea 5.4 is a little to close IMO, the +/- could get you. I like to keep my hydro in the 5.8-6.2 range.

[IMgreen]

the waterfall is incredibly stable isn't it? I love mine! aside from adding water it's almost ZERO work.

ph between 5.8 - 6.2 is ideal

I try to keep my nutes @ 1250 - 1350 until I know what the plants can handle

good luck!