Try the weight method then.
7 gallon soil can hold around 0.7 gallon of water. (You should be able to water at least 0.35gallon per watering, otherwise it´ll probably be too often)
Most common mistake is probably watering too often.
Roots develop much faster in a moist but not wet soil. (yours look a bit too wet)
You can put your finger in the soil to see if it´s still moist and also lift your pots to see how much they weight.
Compare the weight from a completely dry soil...
I had the same thing with some (already rooted) clones, showed mag and cal def in soil which had plenty of both.
My problem was that i had too much light (and maybe heat) and not enought roots (even tho the 250W MH was like 60" away).
Also i watered the soil a bit too much before transplanting...
My Guess is Light too close and low RH.
Maybe try to water a bit less often as well (every 3-4 days seems a bit too often for such small plants in big pots )
Looks like a clear Mag. def. and probably Cal. def. too.
Burnt leaves could be from ph- which could have burnt your roots a bit and also kills your soil life.
But they also could be from Nutrient burn.
Hi, so yesterday i found a link to an Email someone sent to Biobizz with the most common Questions nobody could answer.
Trying to find that Thread here but no chance.
Can someone help me, would like to read it again.
THX
Just from the looks i´d say LED light burn.
The unburnt parts look pretty healthy.
Can you tell me more about the soil?
Mine is a bit washed out (because i recycle it) but full of life, microorganisms and funghi but i wanna freshen it up a bit with more nutrients.
Any recommendations on what...
The leaves look like they had some Cal. def. to me (maybe bit of Mag. def as well, but just a guess because i cant see the lower part of your plant).
Overall they look like they need more grow juice and a steady cal/mag absorption
Could be Boron Def. (but probably isnt)
Maybe they twist the leaves because of something with the light?
Or you got a fan blowing on the leaves?
Truth is, we can only guess with 1 picture no description or additional infos and a light where u cant see the real colour of the leaves
Did the Water where the roots are in get too warm or did they have very low oxygen levels for some time?
Do the roots smell strange and are slimy?
How did the roots look like before the accident?
I´m just speculating but it could be too much temperature and starting root rot that caused this...
How do your roots look atm?
What´s your temperature ?
Is there anything broken on the stem/roots ?
Did the roottips turn brown or anything?
Could it be that the roots didnt get water for some time?
What´s the distance from Lamp to Plant?