Something is still wrong.... pH?

ok. My plants are growing slowly. They are in potting soil until i sex them, then i will buy foxfarm to transplant into. Anyway heres the history... i dont have dates, but im sure there damn near 3 months old by now. I used Superthrive and Pure Blend Pro Grow after the first month, which was when i started having noticeable problems. At first i thought i had mag def so i was adding 2 tbl spoons of espom salt per gal of water for 3 waterings.The i posted a little over a week ago and found out that the labeling on the Pure blend pro gro is up to 4 times more than what i needed, so basically i was over fertilizing. Since then i gave the plants 2 good flushings in my bathtub about 4 days apart allowing them to dry. They are still a little moist from the last flushing but there still getting worse, not better. ive grown b4 and know they should be alot bigger for almost 3 months, but wtf i cant figure this out. I flushed the shit outta them so i know theres no more toxic buildup and they should be getting better. However i dont pay any attention to pH and this may be my problem. any suggestions? I have these pics and can take as many more as needed. I should mention that a few of the plants started showing roots at the surface so i covered them up with perlite, they are all in potting soil. Strains are widow, Jock Horror, Durban Poison , and Ultra Haze #2. lighting is a 400W MH on 24/7 about 1 foot away, turned it back to 12/12 a week ago for sexing. if your still reading, thanks for making it this far

on with the responses, im not sure what other info you need

Thanks

ahh what the fuck... this wont let me upload pics, says a security token is missing or some bullshit, ill try later but basically some of my lower leaves are turning yellow and some have like rust-brown spots. also the tips are blackening....

anyway its saying that the filesize is too big, idk, its a 5MP camera.....

i think your light iseither to close or on too long you should be running a 18/6 light cycle if they are 3 months old..

and even if they dont look that big they will grow 3x there size when they start to flower so happy harvesting...

oh sorry man its not like that, something is wrong, lemme see if i can get the pics on now... they got worse

ok sounds good

finally i got pics to upload! these are from a few days ago, ill take new ones later... thanks for the help

try takin them out of the pot breakin off the dirt were the roots are not growin and then put then in nice clean dirt with no ferts and then give it very little water cuz then need oxygen from being flushed and they should perk up in about 2-3 days i did the same think and it work great

well they are in plain potting soil now, and im almost done sexing them. Once i kill the males i was gonna get some good faxfarm soil anyway.. but im sure the roots have had oxygen because after each time i flushed, i let them completely dry out before flushing them again. If im very careful, can i remove all the potting soil form the roots before i transplant?

you want to do that as soon as you can or it mite be to late