I don't get the water for 3 minute thing every 3 days. You would want to water to runoff and let the pots dry out and get feather light. If you're not getting run off you can get mineral saIt build up.
Add nutes either every other watering cycle or every 3rd watering cycle depending on how they look.
Don't overwater, pot should be dry and light. Use LESS nutes.
You have a combination of shit happening...
And remember to target 78 as day temp., not 70 like you said you have in that other thread. Modify your game plan in the future, avoid nutes for a while on those burnt ones, straight water to excess runoff for a while. Good Luck, they're survivable.