Sick plants Mg? 1st grow

Heres the form;
E-indoor
E-from seed
E-soil
E-specific medium
CSL-Soil type/brand-
SCL-nothing
SCLR-Soil runoff ph-Don't know
E-water-at first distilled water now tap water after 4 weeks left out 2 days
E-Source water pH-Don't know

E-age-~30 days
E-fert-floranova grow
E- .5 tsp/1 G every second watering
E-6 23w cfl 5" from tips,3 pants own pots
E-Air temperature (both day and night if you are running a dark period)day- high of 85 F and night low of 65 F

E-Air % Relative humidity-don't know
E-lighting-first 2weeks 24/0 now 18/6
E-4.5"inline fan ac filter

I'm doing a cabinet grow with northern skunk and the yellowing has begun to spread to the top leaves with some of the older leaves dying off.

My plant is doing the SAME thing. I was thinking mg too. I am gonna start a post with some pics. Hope you get some help.

Definitely try to find a way to check your runoff pH.
It's good you switched to tap water; distilled wter causes problems unless you are adding calmag to it. At this point, I would still add a bit of calmag to the feedings, and also slightly increase your nutrient strength. However if you find that your soil runoff pH is very acidic, you will need to flush well and bring it back up to 6.7 before proceeding.
A foliar feed of any commercial micronute supplement (GH Micro, AlgoFlash regenerateur, Spray-N-Grow, etc.) will help your plants green back up more quickly while you fix the problem.

hey bcsquatter,
there's a way to grow where you won't experience this kind of problem. there's a way you can prevent this kind of thing from happening and you'll take all the guesswork out of growing. the method is this - don't try to do anything special. just get some Foxfarm Fruit and Flower powdered fert at your grow store and put two cups of it in a five gallon container of potting soil and mix well, then put your plants in that and just water them when their thirsty. That will solve 99% percent of your feeding issues.

Thanks for the info I'll check the ph see if thats the prob

Wayward, adding additional powdered fert at this time WILL compound the existing lockout conditions... ???