recovered babies, burnt tips?

Hello, these plants almost died after I believe getting root rot (brown roots?) and I believe I had some too high ppm issues as well. Anyway a few weeks later they are looking better, but the tips look slightly burnt and there are some brown / green spots that are concerning me. They are on 18/6 with pH 5.6 and PPM of 530. Using Dyna-Gro line. Thoughts?

use more dyna-gro to get ppm to 800-1000, ph 5.3-5.9 (5.6 is fine).

Those plants look great otherwise.

Dyna-gro looks so much better than all the larger brands.

the yellowing tips aren't from nute burn? (specifically the 2nd and 5th pic)

nope, unless you were hitting them with like 2000ppm before.

It looks like potassium deficiency to me, but just raise them in general, because if it's deficiency in potassium, it probably wants more everything else too.

okay so bumped the ppm up to 930 wednesday night and here they are as of 60 seconds ago. the new growth is looking pretty good I think. really can't beat Dyna Gro !!

doesnt a red stem go with potassium defieciency? I saw a little red on stem on pic 3 idk if that is normal or goes with deficiency. Im having similar issues with smaller younger plants and idk what to do. Have pics and post in plant issues...take a look

here they are 3 days later. i'm still worried about the green spots