From what you have said and looking at 1 of your pictures of the plant I would say your plant is lacking in Nitrogen, The Symptoms are exactly as you described here and they include poor plant growth, and leaves that are pale green or yellow because they are unable to make sufficient chlorophyll. Leaves in this state are said to be chlorotic. Lower leaves (older leaves) show symptoms first, since the plant will move nitrogen from older tissues to more important younger ones, my advice is to switch to a decent NPK fertiliser, brands I have used with good results are House & Garden, Canna and Advanced Nutrients, good luck and hope this helps.
Johnnycannaseed Reviewed by Johnnycannaseed on . Grow Complications. Not sure where to put this category, since it's now outdoor, I have a problem, and I'm a novice with a lot of "Study" experience. ANYWAYS! So, I'm new to this forum, and the only other Cannabis related forum I've been a part of was an autoflowering one. I've done multiple grows, yet each time they either get into flowering, I either get found out by an intolerant neighbor or the plant dies due to nute lockout. Anyways, My neighbor moved out finally (Thank God.) And now I've been trying to do Rating: 5