First grow - brown spots

[Rip5150]

I'm on day 20 with my first grow, and I have noticed small brown spots toward the tips and edges of my leaves. Does anyone know a possible cause?

Ph: 6.1
mS/cm: 600 (foxfarm grow big)

 

[UrbanGardener]

Possibly a moderate calcium deficiency? Do you supplement with calmag?

 

[Rip5150]

Possibly a moderate calcium deficiency? Do you supplement with calmag?

Sorry, I haven't been on here for awhile. My plant is now a week past flip and has showed her first hairs!

 

[sambapati]

Sorry, I haven't been on here for awhile. My plant is now a week past flip and has showed her first hairs!

Nice hair styling