[Yes, this is my first grow. Im using mg organic potting mix, six 23 watt cfls for lighting, box is properly ventilated w/ 2 exhaust and an intake fan as well as a fan for air circulation, my temp is 81 max, usually around 79, my humidity is 35% at the highest. My plant is 3 weeks and 1 day old. Im not using any nutes. The plant is in a 3 gallon bucket with drain holes. I moved the lights about 6 inches away from the top of the plant because I thought it might be drying it out. The plant feels very dry, the leaves are constantly droopy. Im also having a problem with the bottom leaves getting light green splotches and drying up in certain spots. I dont have a ph meter, yea I know, Its on my list. The leaves are also creasing slightly upwards. Ive been watering every couple of days, only used tap water twice. The soil dries out really fast, but Ive been trying not to give it too much water because I know what they say about overwatering. The roots are already coming out of the bottom of the bucket so I would think it was getting adequate water. Any suggestions? FYI: the lowest set of fan leaves were burned pretty bad and I trimmed them off, They were sitting on the soil where I didnt want them anyway. My camera sux and wouldnt show the light green spots, sorry!!
The reverse cupping is do to one of two thing, or both, high heat stress or light stress. If you can not get the room temp down use some silicon supplement @ 1ml per gallon this will allow your plant to handle higher temps.
If the leaves still cup up move the light higher for a couple of days if it stops then you know it it was both.
The light green splotches and damage is do to not enough N in the soil. The plant is not maintain chlorophyll. Without chlorophyll, you'll have no photosynthesis going on.
To check the moisture stick you finger in the dirt all the way up to the second knuckle, if you feel moisture it still good. If you have roots growing out of the bottom of the 3 gal pot you may have over watered and the roots chased the water strait to the bottom.
Pull the plant out of the bucket and see if the whole dirt pack is held in place by the roots and not just the bottom. If all the roots are at the bottom you need to put you plant in a 5 gal bucket and learn to use your finger.
As for PH water for soil, most good brands of soil will ph buffer the water. Even miracle grow soil ph buffers.
What type of soil mixture do you have?
Does you plant act like it has stunted growth?
If it has a lot of peat moss add 3ml dawn dish soap to your water and it will help retain moisture and balance out the soil.