I’m at around week 9 of my second grow and was really happy with the way things were going until I did the second sledgehammer flush per the fox farm feeding chart. The next day I noticed these dots appearing on the leaves of the one plant and it’s been getting progressively worse over the last week. At first I though some sort of fungal infection but I don’t see any spores or other signs of fungus and you would think if it was fungal then the plant right next to it would be affected as well.

Calcium deficiency looks a little different so I was thinking possible potassium deficiency? I don’t see how that could be with the amount of nutes I’ve been using unless something is locking it out. At first I PH’d everything to 6.3-6.4 but when I did the first flush I slurry tested the medium and it was a little high at 6.6-6.7 so I started PHing to 6-6.2 and by the second flush I was able to get the medium down to 6.4. The day after the flush is when the spots showed up so that’s why I was thinking deficiency/lockout. Could also be fungus but why hasn’t it spread to the other plant with them being almost touching? If it is fungal then is there any saving at this point? I know it’s not pests because I’ve inspected every inch with a microscope lol. Would hate to start over when things are nearing the end.

Seeds were from zamnesia and are autos. White Rhino (left and the one with spots) purple urkle (right). Im using a mix of pro mix hp/cc, Wakefield compost + biochar, worm castings, and basalt dust with a little added perlite, lava rock and coarse sand for improved texture and drainage. Running the full fox farm line of nutrients along with a dose of recharge after each flush. PPFD is between 900-1000 across the entire area. IR lights before lights on and after lights off, UV lights for 2 hours mid day. Temps are 77 (day) 72 (night). Humidity around 50% with a VPD target of 1.5-1.6 for flowering.