Possible Nitrogen or Magnesium Deficiency

[loudog2008]

Hey just noticing a slight deficiency in one of my plants, slight signs in others.

What type of medium; soil or hydro?Soil
What brand and type of soil?Miracle Gro soil with added perlite&peat moss
Indoors or outdoors?Indoors
What strain?Green Crack, White Widow
How old are the plants?one is about 1 1/2 months,others are 2 weeks.
What type of lights and how many watts?T5 HO,4 Bulbs on 4 bulbs off
How far from the lights?3-5 inches
What, how much and when was it fed? NPK?Bigfoot 2 part veg., 2 days ago,N-P-K in nutes is 2-.5-7.6
What is the medium/runoff pH?6-7
What are the temps and humidity in the room?75-80 degrees, not sure of humidity but not too much, nothing that could hurt the plants
What size pots?older plant is in 10 inch as well as biggest clone, rest of widow clones will be translplanted tommorow, hopefully into some FFOF
Any bugs? Look real close.I saw gnats flying around this morning and yesterday but i got rid of them and I have been experiencing this problem since the beginning of this plants growth
Any other pertinent info?

The bottom most fan leaves keep yellowing up and going crispy and every time they fall off the next lowest set does the same thing within a week or so. My other plants are showing very slight leaf yellowing, and the bigger plants older leafs appear to be losing their shine, as you can see in the picture, the bottom yellowing leafs still appear to have green veins.. Any info would be greatly appreciated, thanks

[TexarkanaTim]

How often are you adding nutes? Looks to be a nitrogen deficiency as you thought. Try another mild dose of nutes and see what happens. If it continues to get worse after a week or so, then flush and start adding nutes back at 1/3 or 1/4 strength. If your leaves green back up, then problem solved.

[loudog2008]

I fed the plants 2 days ago and i think today I will just give them straight water and maybe the next few waterings as well to see how it works.I am thinking of getting a new nute system, whats the best out there , i was thinking either the canna system,floranova, or another 2 part. I will be using it for soil for a while but eventually for a hydro ssetup