Brown areas lower leaves. Please assist!

[Vexor1717]

I had previously requested help with brown areas on lower leaves with one of my plants. Now it is on all 3 and I'm getting a bit worried. Looked like phosphorus deficiency but I'm not sure.
All 3 are autos. Grown in Happy Frog, ph 7 going in, 7 in runoff. They are 3.5 weeks old indoor led. Thanks in advance. Also my ppm from tap is 170.

 

[Beachwalker]

Kind of a lot going on there; 4 stocks I think you'd have better results with a pH of 6.5 also it's good practice to take leaves off that are touching the soil

I believe your main issue is over-watering, that is to say the soil is not drying out enough between waterings, gives the leaves a puffy waterlogged look

Lowering pH, & letting it dry out more (search 'wet/dry cycle' on this site) would be where I started, and unless there's something else not mentioned or that I've missed I think that will take care of your issue, good luck