New Grower and plant problem

I have a 3 week old plant that has yellowing and drying leave tips. I am not sure what the exact problem is.

Could you help me Pin-Point it ??

Thank You !!

Have you started nutes? Lighting, soil

In order for someone to help you they're going to need more details. Type of soil, nutes, water type & schedule, lighting, avg. temp & humidity etc. A doctor cannot properly asses whats wrong with someone who is sick without knowing details about the patient.

Puff

Have you started nutes? Lighting, soil how often are you watering?

Ok hehe
The soil is "Enriched Potting Soil" 0.14-0.14-0.14
I am watering with Tap watter once every 2 days
I have not given nutes yet
Lighting is 20-ON 4-OFF
temp is 27-29 degres celcius

With 3x 24 Watt CFL in a computer case

Watering to often once a week is Okay. Nutes everyother watering half strength to start. They need nitrogen so you need nutes ASAP!

I gave her nutes and she is better, I will try less watering

Thank You!!