15 days veg droopy and yellow leaves DWC (pics)

So I am in my 3rd week of veg from seed of Master Kush and I am having issues getting this little baby up and going.
Everything was going good until a few days ago when the lower leaves started yellowing, Droopy and growth slowed. I always have trouble getting a seed or clone established. The leaves have been slowly yellowing after about the first week, I introduced nutes on day 7 at about 350 ppm .5 conversion and worked up to 520ppm on day 14. Roots were growing good into the water and it seems to have stopped as well. Last night I change rez out and dropped ppm back to 350 and killed the light. It has now perked back up but Im not sure what to do from here. Was I underfeeding or overfeeding? Should I jump to 600ppm or leave it around 400? Here is some bud porn to

Bubble Bucket (Tap Water 135ppm)
AN Nutes (Sensi Grow, B52, Voodoo Juice)
350 ppm .5 Conversion was at 520ppm
Ph 5.6 - 5.8 Never over 6.2
400w HPS
Temp 76-79 / Rez 65 degrees
Hum. 35-40% (I have been using wet towels to keep it up)

I would like to add also that the above pic makes it look alot better than what it has. The fan leaves were really droopy almost like an overwatered plant in soil but since the lights been off they straightened back up. Oh and my light is 36" from top in a 2x2 cab.

So what is this telling me when my plant gets happy when I turn the light off.

KrAzY80 said:

I would like to add also that the above pic makes it look alot better than what it has. The fan leaves were really droopy almost like an overwatered plant in soil but since the lights been off they straightened back up. Oh and my light is 36" from top in a 2x2 cab.

So what is this telling me when my plant gets happy when I turn the light off.

Click to expand...

They are locked up and going deficient. You are sure your ph is were it is supposed to be? How do you maintain your res temps? You are sure about your tab water?!
520 ppm seems a bit high to me, especially while they are that small, but that doesn't matter right now since they are locked up.
I would keep the lights a little dimmed until they recover, next do a little flush, next bring them down to about ec .8, and see how they respond.

Kind

Yeah I was wondering if it was locked up and slowly going deficient. I have a Ph and ppm meter and I check that shit all the time. But my Ph has been rising from 5.6 - 6.0 in a day sometimes. I assume the plant is small so it reacts to PH fluctuations more. I just noticed the yellowing after wk 1 progressing so I assumed it was hungry.

How do I know when to bump nutes up again and should I go 100ppm at a time?

Thanks for the advice much appreciated

So just in case anyone was wondering it was locked up. I found an ec above 1.6 was the root of my problem. I dropped it down to 290 and it was good. 1 week later I did a res change and bumped it up to 330 and wouldnt you know I got nute burn. So beware if you are using AN sensi or the 3 part..its extremely Hot. How the hell would you measure .87ml out for 1 gal of water. Not much room for error lol