first time grow hydroponically

my friend has 2 plants that are almost 2 weeks old and he noticed that the inside of one of the plants the new leaves are yellow. what should he do and what could the problem be? he is growing hydroponically. below are pics of his 2 plants is the other one in good condition

make sure its getting nutrients... including micro nutrients. tell your "friend" his plants need more oxygen and more nutrients.

check the Ph its prolly high

a plant that little shouldnt have had nutes at that point, so ph should not be an issue.

superstoner1 said:

a plant that little shouldnt have had nutes at that point, so ph should not be an issue.

Click to expand...

When would be a good time to add nutes because I'm trying to learn from his experience to help me

PPM and PH is important for hydro, your ph should be between 5.8 and 6.0. here's a chart I use for ppm. it gives you a starting point you can adjust as you wish.

PPM for Hanna Chart PPM

Seedlings, Early Sprouts ..100 to 250
Early Vegging ......................300 to 400
Full Vegetation ....................450 to 700
Early Blooming ...................750 to 950
Full Mature Blooms ...........1000 to 1600

yes ph is a very important factor when dealing with nutes. with seedlings all they get is water til they need nutes and ph is not important when dealing with just water uptake.