SUPPORT TICKET - Is this nute burn - lockout - deficiency?

6x The Incredible Bulk strains in rdwc system with chiller and all…
Temperature is usually around 83f (28-29c) and rh 50-60%
Feeding them Sensi Grow A&B.
PH always kept 5.6-6.1

These girls are 7 weeks old now and a bit too short (11-13 inches) and bushy for my taste to go under the net, but I will still try to scrog them next week and probably veg for another 2 weeks or so.

In the first month I went a little too low with the nutes and they showed textbook N deficiency signs while also stunting growth. I started upping the nutes and this time started seeing some burnt tips when I got over 3/4 dosage of what Advanced Nutrients recommend. At first I thought it might be Potassium deficiency so I upped the dosage closer to what they recommend but things seemed to get worse.

1.5 weeks ago I flushed them for 36 hours and cleaned all the burnt/yellowed leaves off. Started dosing with 1/4 of recommended (turned 380ppm) and started slowly upping again. But a little passed the first dosing, I started seeing new leaves with pale green/yellowish look, and some burns… I thought might be a deficiency again and started upping till 3/4 again. But it seemed neither to slow nor quicken the dying process.

There is no dark green look, some leaves seem deficient, some seem to burn but are also showing yellowish color. I’m totally lost here…Is this a nute burn or lockout again, or maybe even too low on the dosage (which is very unlikely imo)…

I need to top up about a gallon daily. Before adding water, I see the ppm have risen but after topping up it falls behind my initial ppm. So they do seem to eat but not as much as they drink. Or maybe the evaporation is a lot…?

Here’s the one with most multi colored leaves, with at least 7-8 leaves burning. No dark green as you can see.
Oh and those weird looking little leaves on top are a result of recent fimming.

As I said, I suspected Potassium deficiency for some time but increasing the ppm doesn’t seem to do any good (or bad). Maybe I should increase it even more but I doubt it… The ppm rises as the water level drops and it’s currently around 950ppm already.

Yet, this little stunted girl (after the initial N def) just started showing new leaves, also burnt tips, but what burns others should have FRIED her… it did not.

I’m suspecting a lockout but I have no idea what to do about it at this point. I already flushed and slowly increased my nutrients and did me no good :frowning:

Strain; Dr. Krippling’s The Incredible Bulk
Hydroponic RDWC - 5 gallon buckets
PH of runoff or solution in reservoir? 5.6-6.2
What is strength of nutrient mix? Problem persisted through 800 → 1100 → 400 → 950 using Sensi Grow A&B
Indoor or Outdoor - Indoor
Light system, size? - 2x KingPlus 1500w LEDs
Temps; Day, Night: Day (83f (28-29c)) Night (10-15f lower)
Water Temp: 64-66f (18-19c)
Humidity; 50-60%
Ventilation system; Yes
AC, Humidifier, De-humidifier: Only Humidifiers working atm.
Co2; No