necrosis problems

This is my first time growing. This plant, which is about 4 weeks old growing under 24 hour CFL light, has had problems like this since its first leaves. I got this soil that had food already in it because it was the only stuff home depot had at the time. It is 21-7-14. The fact that its first leaves were getting necrotic spots makes me think it was some kind of nutrient burn. I gave the soil a good flushing with fresh water some time ago, but I doubt I got all the time release nutrients out of the soil. It is affecting new and old growth all over the plant.

What do you think? Is it possible it is still nutrient burn or is it some kind of deficiency? From this page International Cannagraphic Magazine Forums - The Complete guide to Sick Plants,pH, and Pest troubles! it looks like maybe calcium.

my thoughts are that it is either a problem with irregular watering or some sort of root problem. cheap soils tend to harbor bugs and rot. if the soil stays wet all the time then you haqve rot problem due to improper drainage. if not then i would suggest de-potting carefully inspecting the roots for dead/decaying roots and bugs crawling around. if these are your problems then you should carefully remove the soil from the roots and xplant into a fresh pot of organic goodness with plenty of earth worm castings, humic acid, and beneficial microbes. add RO water with superthrive or some other b1. happy growing

change the soil i know got some cheap crap to fucked everything up also get some with no nutes add your own a little work but u will love the out come no mircale grow good luck hope ev everything goes good