i have moderate experience id say,,, i have been growing for over a year..all diffrent kinds...
ph is around 7
air is 15 air changes per minute
temp is around 25-27c
im using metalhailide for veging 400 watts about 1 foot away 30 - 40 cm
for flowering im using hps 400w also same...
Mn is Manganese.... it kinda looks like it....
i dont think its the nute burn because its the same soil i always use.... it does contain time release fertilizer...
this doesnt explain how all the plants almost have the same problem even the ones without any fertilizer yet....
some of these plants never even had any nutes...
plus this seems to be spreading to other plants... even the ones in flowering...
one more thing... this seems to affect only older leaves....
Im thinking Mn problem....
recently many of my plant are exhibiting symptoms i cant be sure of....
here are some pictures.. please take a look and let me know what you think...
as soon as possible please...