Leaves curling up, twisting and yellow spots!

[polysantiago]

Hey guys, this is my first post even though I have been reading the forums and has been my main source of information for my first grow!
I come to you now in seek of help because almost all my plants are having the same symtoms: leaves curling up and some of them with yellow-brownish spots!
I'm 2 1/2 weeks after germination (strains White Widow and Blue Mystic). Here are the specs of my grow room:
- Medium: Soilless mix
- Nuts: 1/2 dose of Hesi TNT and full dose of Hesi Root Booster (after 1st set of true leaves)
- Room Temperature: 23-25°C
- Light: 2x55w fluorescent lights
- Feed schedule: water, water, nuts (feed only when 1 inch of medium is dry)
- Oscillating fan to keep air flow

What I don't have (yet):
- A PH meter (cannot test the PH of the water or the medium).
- Distilled water: I'm using tap water since it's supposed to have a neutral PH (bottled watered doesn't even exist here)
- An EC meter
- Intake and exhausting fans
- Hygrometer

I know I should have the material about but not only I'm on a tight budget but also I've orded some stuff that hasn't arrived yet.
So, with the information provided above, what do you think could be wrong with my plants? is it serious?

Some pics:



Please, don't hesitate to ask for more information if I've missed to provide some.

Cheers!

 

[Hydroponic1]

My first thought would be a calcium or magnesium def. I dont know a lot about soil but you may want to check the plant abuse thread for some help also. Plant Abuse Chart Good luck looks like you will catch it in the early stages.

 

[polysantiago]

Yeah, though about Mg def but wasn't really sure. Where can get epsom salts? At the supermarket?
And by the way, thank you for your quick reply, man

 

[Hydroponic1]

yes you can get it at the supermarket or drug store. Cal Mag is an awesome product which you can get at your local hydro store if you have one.

 

[polysantiago]

I'll see if I can get Cal-Mag. Otherwise, I'll stick with epsom salts.
Don't you think it could be PH related? Haven't been able to check the soil/water PH and that's really disturbing me...

 

[Hydroponic1]

its possible but ph usually dosent cause curling

 

[420 Junky]

I don't know what soil-less mix you're using, but those purple stems got me a little concerned? Could be a number of things. Do you have a fan blowing directly on it? I also don't know much about the fertilizer you're using, and where are you getting your water from? Is it tap water? Oh yeah, every grower should have some Epsom Salt around. Dissolve a tsp in a quart of water and give it a drink. Perhaps thet'll do the trick.
As for the brown spots, looks to me like something took a little bite which made the tip of the leaf curl. No big deal. Just make sure you keep the space clean.

Other than that, the plants look good.