Couple of different issues with leaves

Hi all,

I have 3 Tropicana cookies in flowering stage, I think in about week 7. I am experiencing drastic yellowing of leaves and the sugar leaves are starting to go yellow, especially on the tips.

I also have 2 Mazar and 1 Grand Daddy Purp in vegetative stage. I am now starting to see the leaves of these getting brown spots. The 2 Mazar are getting similar brown spots whereas the GD Purp seems to have some misshapen leaves. The 2 Mazar are growing pretty sluggishly. The most concerning thing with my veg plants is that the new growth is showing brown tips almost immediately.

I grow in soil, the flowering plants are under a 150w hps and the veg plants are under 300w full spectrum led. I’ve been using Orga Grow Holland fertilizer - Root power, healthy growth and abundant flower. I try to use half the recommended amount, and ph balance the water to a low 6. I did accidentally put some osmocote in the veg stage soil as well. I have also juststarted adding a little bit of cal mag (was late to the party with the cal mag).

I am having lots of trouble trying to keep the PH in the 6-7 range, it always seems to be creeping up above 7, then I get paranoid and try to balance it and then I feel like my plants are always too moist. I also have some flying insects in the veg set up, I’m spraying with berm oil to try and get these under control, but it’s normally only like 3-4 buzzing around.

In short, I don’t really know why I’m having so much trouble with my leaves and plants. I also don’t know why my PH is always creeping up. I use an analog PH probe to measure my soil ph, so maybe I’m not measuring accurately enough. I don’t have any kind of run off info in regards to PPM.

Any advice would be much appreciated, sorry if I’ve left out some vital info. First pics are the Tropicana cookies, next is Mazar (fat leafed ones being grown using manifold technique) and then grand daddy Purp is last (the one not in a grow bag).

Some more photos.