N-burn, K-deficency, something else?

[InuYasha]

I had it narrowed down to pH and a K deficiency. I got a new pH meter. I was keeping my pH a bit low, I'm now confident that I have it at 5.8 (really 5.7-5.9 with the +-.1 error). I added some Gro Tek Pro-Silica because it was the only thing I could find to raise K without adding more N and P. So far, the new growth seems alright, but most leaves over 2 weeks old show some small amount of burn. The plants still seem to be growing well, so I'm less concerned. I'm switching nutes from GH Flora-Series to Grotek Solo-Grow, so I'm hopping whatever deficiency I may have had will be corrected.

Here are the latest pics of the problem leaves:

 

[BigSmoke41510]

^that helped me out thanks! Im having the same problem, im gonna try to increase my PH a little bit and see what that does, im also using the color test which i am starting to hate lol

 

[InuYasha]

After nearly 6 weeks of very subjective colour matching, I've come to the conclusion that the colour test sucks. It's fine for getting "in the ball park", but I don't think I've ever guessed within .2 pH of what my meter tells me.

Maybe it would be good for an interior designer, painter, or someone who can tell at sight the difference between 'creme' and 'eggshell', but sadly I'm not that talented.

My new growth looks better at a confident 5.8. Still some light burning / spotting of the older growth, but 80% less sever than before. I'm also going to try a Ca/Mg/Fe product to see if I can't get 100% spot-free leaves.