HELP! Unidentified leaves problem!!

[kakolukia]

hi all. this is my first DWC grow and i ran into problem with leaves. the plant is CINDERELLA JACK. she is 2 weeks old and lower (older) leaves started dying. please help solve this problem...
i use 30 liter water reservoir with air bubbler. 2000 watt led equal to 1400 watt HPS. distance from plant to lamp is 70 cm. i check ph and tds twice a day. i use tap water with 120 tds + general hydroponics flora trio + calimagic + hydroguard according to chart provided by growweedeasy.com. can anyone identify my problem?

[alltatup]

Hi there and welcome to the forum;

I'm not sure what the problem is, but this looks like a possibility?

https://www.growweedeasy.com/yellow-...-leaf-septoria

If I were you, I'd look at leaf problems on GWE and see what matches up to your plant.

[Flockshot]

That is a phosphorous deficiency. It could be a shortage of P in your system, or the plant is unable to uptake P. Just my opinion.