need help for my kids

[1stgrower]

its been 15days

leafs getting dark and yellow .

I dont know whats going on.

need help for my kids plz~

 

[BuddroGreen]

What are you feeding?

pH?

 

[crankz1]

Over watering, and the roots are starving for oxygen.

 

[Dan Ultra]

Need more info. Start by filling as much of this out as you can

How many plants? What Kind?
How old are they?
Indoor or outdoor?
How big is your area if its indoors and is it well ventilated?
What medium/soil are you using?
Whats the size of the containers?
What's your lighting set up?
What's the temperature and humidity like at any given time?
What's your pH like, both medium and nutes?
What's the NPK of all your nutes?
How often are you feeding with nutes?
Any pests around?
What is your watering schedule ...