Me and Scf have a little history, i helped and guided him a bit on his led conversion and mostly he hit the ground running. Good to see you over here, buddy its a lot more fun than riu nowadays.What rocket soul said above. I had these very issues after the switch and following his advice it sorted my girls out.
Higher calmag, slightly higher PH. Getting run off PH and EC in check with what the plant was actually using.
Deficiency can be tricky as symptoms may be because of lock out due to other factors vrs not enough supplementation
@ReprobateMind
Yes, led burn. Its hard to fix what has already been burned. Scf answer is good; but id like to add onto it. You likely have to use a bit higher nutes in total. Led plants just drink less in general if you dont play around with the environment (higher temps both for drinking and metabolism, more attention to vpd). If they drink less then the juice must be more concentrated to get the same amount of nutes in total. So you kind of have to strike a balance between pushing climate towards more drinking (which can be complicated) and upping your nute levels; at least a bit more calmag relatively, and likely all a bit higher total EC. But upping nute levels means you have to pay much more attention to salts in your grow medium, check run off everytime. Its so easy to go overboard and be in the land of going between defs and toxicity/lock out. Another thing to pay attention to is if the climate changes towards more transpiry your plant will suddenly drink more of the strong juice and get toxicity. This why i dont rec the organic soil approach to starting out with leds its just so hard to adjust when you cant control all the nutes in the soil.
Or you can go the way of both Ca and Scf and use mixed lighting. Its a very good way. If you dont have space for a full cmh/hps load out you can even try to drop a little incandescent watts for heat and reds. But carefull with wattage as too much and youll get bolting. Look at Grey faders last grow for an example, its a sight worth seeing
Another reason for higher nutes is that with your new led light most people are hoping for improvements, higher intensity and yield should always warrant more nutes. But thats just part of pushing your trow further.