Yellowing lower leaves

I don't know what it was that caused my plants to do this I just watered my plants with ph water and it seems like the plants are doing fine it could either be not enough water or to many nutrients. I am using ocean forest and that might be the cause.

This also looks alot like chronic underwatering. I'm curious if they have had a good drink near the base of stem? I looked through your diary and your pictures look very dry.. Also you really don't need alot of recharge.

@jpeero is 100% correct. Upon further review, it does look like an N deficiency. Thay said, it could be an N deficiency either way; too much or too little in your medium. I'll defer on which to smarter growers, lol.

Do you know the PH of your soil / water going into it? I would be thinking its either nutrient burn or the opposite that you need to add something. Be careful in what you decide. Maybe just stick to ph'd water for now and see if it gets better or worse and then provide a solution? The dark green leaves and curling downward tips represents nitrogen toxicity. The lower yellow leaves might be a sign of magnesium deficiency, or might just be part of the nitrogen toxicity, however it is lacking the accompanying red stem. Occasionally a nitrogen toxicity is mistake for a deficiency, but I do not believe that to be the case here. I did a little research on your behalf and think I found more relevant information. From growweedeasy.com: A light green or yellow coloring will begin to show on the veins and edges of the lower & older leaves – this is one of the classic signs of cannabis magnesium deficiency. You may also see red stems. If you don’t react to it promptly, a cannabis magnesium deficiency can spiral out of control and cause your plant to lose a lot of lower leaves quickly. The plant will pull magnesium out of older leaves and bring them to the newer leaves. That’s why a magnesium deficiency usually appears towards the bottom of the plant and on older, less important leaves. The edges of the leaves may become yellow or bright green and may start feeling crispy to the touch. This crispiness around the edges is different from nutrient burn, which does not lighten the margins inside the leaves. You may see red stems with a magnesium deficiency, though not always. Problem: Dark green leaves, shiny leaves, clawing, weak stems, and overall slow growth. Marijuana leaves that are nitrogen toxic often get “The Claw” or talon-like leaves that are bent at the ends. They also do an odd curving (or cupping) that is often mistaken for overwatering, but is unique to nitrogen toxicity. You can see a “clawing” leaf in the pictures below (click each picture for a close-up)." Hope this information helps you.

You're using 1/3 peat moss, which is a dense substrate that can hold onto nutrients very well. It could be you're going too hard on your watering, and they're building up in your medium. It's also dependent on how you mix them I suppose. If the roots hit some of it, and it's loaded with nutrients, it could cause burn on the plant. That said, yellowing can also be a sign of cal-mag (if accompanied by brown spots) or iron deficiency. Iron deficiency tends to show as yellowing in new foliage, where as magnesium deficiency turna new and old growth yellow. I'll leave proportions of nutrients to the experts as I'm still learning myself, but that looks like a magnesium deficiency to me. 1 teaspoom of Epsom salt per gallon of water, sprayed foliarly could help.