Ok I'm desperate now!

I can't figure out what is wrong with my plants. They are about 3 weeks old and the bottom leaves are turning yellow, then black and falling off. I'm using 3 different kinds of soil so I doubt that. I've tried varying the water schedule even. My one plant that was completely healthy is now turning the lower leaves black. My 600watt hps is plenty far away, I've varied that as well. These plants aren't going to do very well at this rate. Some are 1/8th the size of others and have barley grown at all. What am I not thinking of?

Well Tadaa,

You will need to provide a little more information for anyone to put the finger on your problem. What have you feed them, how much, what size pots, what your ventalation setup? Maybe most likely one of these items will need to be addressed.

Loco

Sounds like a PH issue to me, what's your PH at?

what kinds of soil are you using, is the wtaer pHed?, nutes ect

get some pics up

GG23

Well the thing is I've used this soil before for my first grow and zero problems, I also have a friend currently using one of my soils for his grow and he has zero problems, and less ventilation than I do.

I'm not sure of PH, but like I said I've used this tap water before for my first grow and had zero problems. I will take some pictures tomorrow and bump this, thanks guys.

first,how do u water? do u flood each watering,if so check them on a weigh scale,as wen they droop for water.if u do flood,and plants are taking up waterkinda fast ,but plant lookin not growin properly,too much water.now if flood methodnot workin,try measuring the amont ur given now,and on next water reduce that amont by 1 ounce,eah time until plants lok better.u can also find out how much water ur soil holds,and give them 1/2 that amont.then some people lik uncle ben,watering twice a day?it works for him,but ull be dam if ull be doing that,i just dont water that much.i dont flood my plants,wen i water ,i only flood wen i transplant to 4inch pots,or 6-12 inch pots,on the third watering,then ever watering after that,a few ozs-4oz or 4inch pot-6inch,8ozs for 12inch pot,the monts can very with row conditions,under florescents,and 70 watt hps.i had a problem similar to urs,i started i seed starter cells ,everthing fine,but wen i transplanted,to 6or 8 oz cups,everthing ok,but not doing really well,then to 5inch pot,lik i did for last three yrs,then, all sudden not workin,at all,played with the watering and nothin,somes transplan to 4inch sq. pots,2inch of strofoam,on bottom,and the rest poting soil,sams choice,then presto everthing is fine,then went to 6inch pots,good to go.i knew how to adjust watering,and fine tune,my last option worked well,maybe that can help ya,been there and done that.wen eerthing wasnt workin i changed pot sizes,for first time in three yrs....shewww.....peace buhead and the beviss/crusader....:) :cool:

people water diff.,wat works for them.i seen were ed rosenthal,only gives his 12 inch pots 8 ounces of water,straight outa hightimes,so not ever one floods pots,so do ome dont,wat ever way works for u.by the way my tap waters ph is 7.4. xxxxxxx

I had a similar problem on my last grow, i flushed with plain water, and then used a high nitrogen fertilizer for folowing watering, i thought my problem may have been excess salt build up but I never found out