Advice for some leaf yellowing

[golfer420]

Growing two NL Auto's that are on day 19. They're both in soil in fairly small pots (6" high 6" across). Check out my grow journal for more details room details and pictures.

On Friday 3/32 I put 1tsp Fox Farms Big Bloom into 500 ML of water and ph balanced (for each plant). Poured the entire 500ml into the plant (pouring around the outside) and then disposed of the run off after about 5 minutes.

Left for three days and returned today and noticed the coloring on a few of the top leaves of plant 1. Looked like it might be magnesium but I'm not sure (potassium looks possible too).

I'm assuming if I put too much BigBloom in that it would have looked worse after three days.

Currently under 4 23w CFL's and 1 18w LED. Getting a 300w LED panel in a few days.

Thoughts?

View image in gallery​

View image in gallery​

 

[Conradino23]

This is calcium deficiency caused by excessive potassium levels most of the time or poor mineral content of your soil.

 

[golfer420]

Thanks, Coradino! A couple days later now and those few leaves no longer have that distinctive yellow. I'm always adjusting the ph of the water so maybe its improved so it can absorb calcium.