Need Help using Jack's Classic Fertilizers Veg. 20-20-20 and Bloom 10-30-20

I have heard to use one quarter strength and other things people have suggested. I was hoping that someone familiar with Jacks could tell me. I've been having problems with both yellowing and what appears to be burning on the tips. I'm confused because I just got a PPM meter and it seems that I haven't been giving them enough. I'm just worried to use more. Could someone please help? Thanks so much!

Is your PPM meter calibrated?

I have always started with Jacks at 1/2 strength for my first feeding. After that just go with the recommended 1t/gal
I would use the all purpose 20-20-20 while in veg. After about 2 weeks into flower I will then switch to Bloom Booster 10-30-20.
Always worked for me with never any signs of nute burn or lock up. Just make sure that a few weeks before harvest you stop using ferts altogether and flush with straight water.
The yellowing you are experancing may be due to a lack of N. Start with regular feedings of Jacks 20-20-20 and I will bet it would go away.

read my nutes on a budget thread (sig link) it's all about Jack's