Any ideas

I have been getting quite a bit of yellowing on mostly bottom leaves.
Kind of hard to tell what it is. My plants are in quart containers and some of them are not full. The potting mix I am using was working very well at first but it seems now to not hold any water at all. I have also added more ventilation.
My medium is staying about Ph6.4. I have to water most of them every day. they will be completely dry and wilting. I have been feeding them miracle gro and miracid. I sometimes add epsom salts for very hard waer and lemon juice to bring down the Ph. This looks like it could be either lack of nitrogen or over nitrogen. Because the plants are in such small pots I am wondering if they exhaust their nutrients faster than normal. I would really like to get this fixed before going to flower.
I am very definately not overwatering.
Any ideas?
Thanks,
CD

Well your right it looks like they want N

but it might also that they are root bound in those pots and can't get enough nutes

then too it could be the epson salt if you are watering with it everytime

I would get em in bigger pots after flushing them with distilled or RO water, you can get distiled water at any grocery store for less than $1 a gallon, my walmart has RO water and you can get 5 galons at a time

Why miracid? true MJ is a bit more acid than alkaline but never heard of it being used for growing? so could be that, I would stop using it

what is the NPK of your MG fert?

I only used the epsom salts once with a pince more a couple of times. I dont think the magnesium is too high, I am leaning to N starved is the problem. I have taken great pains not to over fert them and more and more I am thinking that they suck the food and water up quickly in the smaller pots. Cant really go to larger pots until I get more room when the plants show sex
Thanks
CD